Let's build a drag race 8BA engine

[HopRod]

So, I am in the planning stages of wanting to build a drag race only engine for 1/8th mi. I have an 8ba block, 1115 Edelbrock heads, a good set of stock rods, 3.75 crank, and a 3x2 intake. I am fully open to any and all ideas as far as cam, displacement, compression, different rods, etc. What are your thoughts on a 255 higher rpm vs a 296 engine?

I know racing flatheads is not a cheap endeavor, but money is not unlimited here. I want to go have fun by building a reliable motor and turn some decent times. I used to race a front engine dragster with the VDRA in Colorado that had a flathead with a powerglide trans. I have since relocated to NC and am starting a new project.

Let's have a discussion and see what ideas are out there.

[51504bat]

Search the posts here on the Barn by @roseville carl regarding his blown FED with an automatic.

[Ronnieroadster]

HopRod welcome to the Barn.
Since I have dabbled a bunch in a number of fast straight line flathead powered rails heres my thoughts.
To achieve some type of decent MPH and ET your going to need RPM and horsepower. Unless the rail is extremely light less than 1000 pounds which realistically is not possible being only multi carb your extremely limited on what you can achieve.
Being in North Carolina most tracks you will run on I think will be 1/8 mile. So first off your going to need a rear gear thats well north of 411. My choice of power adder to the flathead would be a 471 GMC blower with a decent size Holley dual feed four barrel carb on top. Running a blower drive ration around 12 percent under. You could use a decent stroker crankshaft but most are offshore quality or stay with the 3-3/4 Ford crankshaft which I have found o be extremely strong for most blower combinations. However the rods I would use would be aluminum and the pistons forged light weight possibly from Ross the bore at least 3- 5/16. This would give you a 258 cube combination with the blower the crankshaft HP will be over 300 easily. Now if this is something that sounds good for you I can help you with every part needed for the blower combination. I have plenty of 471 blowers and the intakes for the Flathead in stock and can easily assemble the required drive assembly complete. Theres lots more I could write but for now lets see where this goes. I would suggest one more thing pay attention to information you get. Your looking for ideas and input from the very few individuals here on the barn who actually have the experience needed to give you guidance
Ronnieroadster

[KiWinUS]

HopRod where in NC. I’m in Charlotte & may be able to help.
Thanks
Cheers
Tony

[flatheadmurre]

How much do you want to wrench and how much do you want to spend...
If you want to have fun and not open up that engine on regular basis i would stay away from aluminum rods...H-beam steel rods goes a long way if you´re not going to compete all in. Aluminum rods are lovely and fairly priced but they are sensitive to nicks, stretch and have fatigue issues which will have to be checked regular...just saying.
All in competition you are easily spending north of 12k in a blink...just a billet crank is 3k..rollercam setup another 3k...rods and custom pistons...
If you could get Ronnie or someone seriously competing to help you what they have outgrown will be a perfect start for you and probably a bit friendlier to your wallet...just my 2c.

[petehoovie]

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Originally Posted by HopRod

. I used to race a front engine dragster with the VDRA in Colorado that had a flathead with a powerglide trans. I have since relocated to NC and am starting a new project. Let's have a discussion and see what ideas are out there.

[nickthebandit]

Ronnie Roadster is a well known flat head builder and racer. He and his son own flat head records at Bonneville. listen to what he says, he knows what he is talking about.

[Tim Ayers]

Originally Posted by nickthebandit

Ronnie Roadster is a well known flat head builder and racer. He and his son own flat head records at Bonneville. listen to what he says, he knows what he is talking about.

Second this. It's unreal what he is doing and it is amazing the parts that he has lying around "in stock"?

[Pete]

Ronnieroadster has a good budget build suggested.
One place you do not want to skimp on though is the cam and valve train.
A 425 with lightened stock lifters is probably the best flat lifter cam you can use. Most of the top doggies in the past used it. A radius lifter cam will go faster but is extremely expensive. Roller cams will not perform as well in a flathead Ford drag race engine as flat or radius lifters.
Aluminum rods are good but have a shorter fatigue life than forged steel H beam rods.
Before you buy pistons, you need to decide what fuel you are going to run and stick to it, especially with a blower. The compression ratio will be different with a blower or naturally aspirated. Alcohol is cheapest at about 2 bucks a gallon. Race gas 10 bucks or more. AV gas about 6. Street gas about 4 right now. On a budget, don't even think about nitro.
A front mounted ignition or mag will be more trouble free than an 8ba type.(no extra gear set to go through)
Use 45 degree sweptback "zoomie" type headers like the top fuel cars. They give some downforce and forward push.

[Lawrie]

We use a scat 4in crank and rods with ross forged pistons ,a 471 with hilborn injection on straight methanol ,A VERY reliable setup, run 13 psi boost ,home made heads,
last meet ran 9.4 @ 140 mph in the 1/4 mile.
Lawrie

[HopRod]

Wow, great feedback so far. I should have added in my original post that it will need to be naturally aspirated and is going in a Gasser. I am building this to race with the Southeast gasser association in the H/Gas class. I had bought a roller car, a 58 Morris Minor that was set up for a SBF, so I am converting it to flathead powered.
I do have a 4-71 ready to go, but that is against the rules. This new engine will need to run on race gas and I will have a cooling system for the car. It will be backed by a Muncie 4 speed trans and I have a set of 514 gears for it which should get me in the ballpark. I have heard people have had good and bad results with SCAT or Eagle cranks for reasons of balancing issues or just failures. I love to hear from the experienced crowd who have actually done it, not just catalog parts assemblers.
In my dragster, I ran 3 stromberg 97s that I converted over to use with methanol and even ran 20% nitro one time in it. I never to got to realize its full potential since I was learning as I went and didn't quite have my combination sorted out.
Hoping to be better at setting up the full package from the start this time. I think I would like to stay away from Aluminum rods at this point, so would you suggest race prepping the factory rods or go with a set of H beams?

[HopRod]

Originally Posted by KiWinUS

HopRod where in NC. I’m in Charlotte & may be able to help.
Thanks
Cheers
Tony

I live in the Raleigh area and would love some of you advice/expertise. I actually bought a L100 from you a while back.

[grumppyoldman]

I was wondering why you need a cooling system. Are you going to run it on the street or just drag strips? I knew an old guy from Sulpher La. that ran a flathead in a 40 coupe with no cooling system. The block was filled with cement, he was never beat that I know of, very fast in the 1/4 mile and that was in 59. He never told his secret about how to make the flathead run. Al

[Pete]

If you do not want to weld and re-machine the heads for flat top pistons, you can run av-gas. (100LL)
It is MUCH cheaper and will work with 10 to1 compression and your Edelbrock heads very well.
What crank you use will depend on how big you want the engine and the amount of money allotted for it. For a NA gas engine you could get away with a welded stroker just fine and that means you could get up to 352 ci or anything less.

3 carbs will get you going but 4 would be better. Use 48's if you can find them. Use the new 250's if you can afford them and Hilborn injectors would be best.

Go with new forged H beam rods. They can be lightened quite a bit. Even the best prepared stock rods have a very limited life in a race engine.

BY THE WAY, LOSE THE COPPER BRAKE LINES. Most racing associations will not allow them anyway.

[Lawrie]

We ran our old engine in the dragster first up for about 4 seasons, used an 8ba block, stock rods and crank, bored to 3/5/16 with ross forged pistons,hilborn injection, potvin eliminator cam, would run around 115 mph in the 1/4 , 5800 rpm at the finish line, never missed a beat.
That engine is now sitting on the bench next to the coffee table.
Lawrie

[Ol' Ron]

Your biggest issue is: The intake ports and manifold. It's the limiting factor in getting air into the engine. The bigger the engine the bigger the problem. That's the reason the blower really wakes up the flathead. Us rodders have been looking for the "Holley Grail" here, but so far it eluded us. Good luck, have fun

On a side note. Ibuilt a 258 Hydro engine, similar to our Danbury engines, only abigger valve was used and dual carbs. Boat ran in the hi 50s low 60 MPH. Engine turned 5500 Plus.
Owner was concerned with the family jewels,in/out box was between his kegs.
I b build a 284 /L-100 cam and Mike Davidsons Heads. Pulled 175 @4800 and never saw 60 MPH again.. I blam the prop, but i could be wrong.
Gramps

[KiWinUS]

HopRod you may want to check with Quain on H/gas rules if you haven’t already. H/gas in SEGA has a stock head rule.
Look forward to talking in the future.

[HopRod]

Originally Posted by Lawrie

We use a scat 4in crank and rods with ross forged pistons ,a 471 with hilborn injection on straight methanol ,A VERY reliable setup, run 13 psi boost ,home made heads,
last meet ran 9.4 @ 140 mph in the 1/4 mile.
Lawrie

Lawrie, which SCAT crank did you use, did you have a billet one made or is the series 9000 cast steel?

[HopRod]

Originally Posted by Pete

What crank you use will depend on how big you want the engine and the amount of money allotted for it. For a NA gas engine you could get away with a welded stroker just fine and that means you could get up to 352 ci or anything less.

Go with new forged H beam rods. They can be lightened quite a bit. Even the best prepared stock rods have a very limited life in a race engine.

BY THE WAY, LOSE THE COPPER BRAKE LINES. Most racing associations will not allow them anyway.

Who can do a welded stroker in this area? Not sure what the cost would be, but seems very labor intensive. Cost maybe between a Moldex and an Eagle crank?

I am convinced to use H beam rods, so need to do some research on those.

I don't have copper brake lines, they are Ni-Copp, a Nickle/copper/iron alloy that is fuly DOT approved.
Thanks for info Pete

[JSeery]

I read through the H/gas rules, seems like a tuff class for a flathead. If I'm reading it correctly they include OHV I6 and 4 cyl (about anything 67 or earlier including VW). A Chevy OHV 6 can put out some power! When we were racing our B/altered (mid 60s) there was a flathead altered (D if I remember correctly) that ran local. I6 OHV were allowed in the same class and it was very hard for a flathead to run with them. We also (later) ran a 2300cc 4cyl overhead cam engine. It would run 9000 rpm easy and I think around 230 hp. Again, not easy with a NA flathead. Tuff to compete with more modern engine designs.

[Pete]

Originally Posted by HopRod

Who can do a welded stroker in this area? Not sure what the cost would be, but seems very labor intensive. Cost maybe between a Moldex and an Eagle crank?

I am convinced to use H beam rods, so need to do some research on those.

I don't have copper brake lines, they are Ni-Copp, a Nickle/copper/iron alloy that is fuly DOT approved.
Thanks for info Pete

I don't know who is doing welded cranks now but I used to get them from Hank the Crank. Whatever crank you choose, when you balance it, you want to make the bob weight as light as possible.

Better make sure the racing association rules are ok with that brake line material. You are not racing with the DOT.

Here is a pic of what can be done with Cat H beam rods to lighten them.

[Yoyodyne]

Originally Posted by Pete

If you do not want to weld and re-machine the heads for flat top pistons, you can run av-gas. (100LL)
It is MUCH cheaper and will work with 10 to1 compression and your Edelbrock heads very well.

Does this mean if you go flat top you can get a higher C/R?

[Pete]

Originally Posted by Yoyodyne

Does this mean if you go flat top you can get a higher C/R?

Yes.

[Brian]

Pete, Can you please elaborate as to why, running flattops, allows higher compression ratios? My 255 running flattops sure is a rattly thing.

[Lawrie]

Hoprod, we just use the standard 9000 series scatt one, so far about 10 seasons and no drama ,touch wood. only thing I would change is we used the scatt H beam rods with the 2.00 journals, I would rather have used the 2.139 journals.still it all works fine.
Lawrie

[Tim Ayers]

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Originally Posted by Lawrie

Hoprod, we just use the standard 9000 series scatt one, so far about 10 seasons and no drama ,touch wood. only thing I would change is we used the scatt H beam rods with the 2.00 journals, I would rather have used the 2.139 journals.still it all works fine.
Lawrie

2.00" allows for the use of the Buick bearings, right?

[JWL]

I think JSEERY has provided the realistic advice you should be aware of before deciding what to build. If you want to be seriously competitive in the 11 lb. class there is no niche for our Flathead V8 engines.


If I was motivated to compete for wins in that class I would use the Pontiac OHC from 1967. If I just wanted to show up and have fun, and didn't care about being beaten by about half the track, I would use my Flathead.


If you are stuck on the Flathead determine the minimum weight you can build the car to and will fit an engine configuration. For example the 239 cube Flathead must weigh around 2650 lbs. That combination will easily outperform a 296 cube at 3275 lbs. when both engines are built to the maximum performance level. Forget about strokers.

[Pete]

Originally Posted by Brian

Pete, Can you please elaborate as to why, running flattops, allows higher compression ratios? My 255 running flattops sure is a rattly thing.

It is simple math. A flat circle has less area than a spherical (raised) circle.
To do this you need to either fill a dome head and machine flat or make new heads with no dome.
Another advantage of flat top pistons is the flame front will travel faster over the
shorter flat surface rather than a domed surface.
This is nothing new, The NASCAR guys were doing it in the 50's.

[Yoyodyne]

Originally Posted by Pete

It is simple math. A flat circle has less area than a spherical (raised) circle.
To do this you need to either fill a dome head and machine flat or make new heads with no dome.
Another advantage of flat top pistons is the flame front will travel faster over the
shorter flat surface rather than a domed surface.
This is nothing new, The NASCAR guys were doing it in the 50's.

How much higher can a comparable combination be with flat tops over domes? 1/2 point or more?

[HopRod]

If you want to be seriously competitive in the 11 lb. class there is no niche for our Flathead V8 engines.
I have been told I would get some weight breaks and come and have fun.

If I just wanted to show up and have fun, and didn't care about being beaten by about half the track, I would use my Flathead.
The class is still growing and there are various levels of performance in the class. I am not chasing prize money or trophies, I just want to run my car with others that enjoy vintage motorsport. I will end up mostly competing against myself to see how fast I can make it go.


If you are stuck on the Flathead determine the minimum weight you can build the car to and will fit an engine configuration. For example the 239 cube Flathead must weigh around 2650 lbs. That combination will easily outperform a 296 cube at 3275 lbs. when both engines are built to the maximum performance level. Forget about strokers.[/QUOTE]
Why forget about strokers???

[Pete]

Originally Posted by Yoyodyne

How much higher can a comparable combination be with flat tops over domes? 1/2 point or more?

It depends on the size of the engine. Simple math will tell.

[HopRod]

Thanks to all those who responded, I really appreciate the feedback.
What should be done with the main bearing caps? do they need to be replaced with aftermarket steel caps or would a center main cap support be sufficient for an under 5800 rpm engine? Would that also be dependent on the weight of the rotating assembly; i.e., bore & stroke?

[Pete]

Originally Posted by HopRod

Thanks to all those who responded, I really appreciate the feedback.
What should be done with the main bearing caps? do they need to be replaced with aftermarket steel caps or would a center main cap support be sufficient for an under 5800 rpm engine? Would that also be dependent on the weight of the rotating assembly; i.e., bore & stroke?

Anything is better than stock.

1- Straps with screws. Good
2- Simple center strap girdle. Better
3- 2 steel caps. (front and center) Rear with strap and screw. Better yet.
4- Full pan girdle with integral caps. Best.

There are some variations of these also.

[GOSFAST]

Originally Posted by HopRod

Thanks to all those who responded, I really appreciate the feedback.
What should be done with the main bearing caps? do they need to be replaced with aftermarket steel caps or would a center main cap support be sufficient for an under 5800 rpm engine? Would that also be dependent on the weight of the rotating assembly; i.e., bore & stroke?

Here's a "link" (https://www.fordbarn.com/forum/showt...le#post1878599) to some reading about a build we did some years ago!

I still have the "pattern" here with me. The final installation was done without the necessity of align-boring OR even align-honing the mains!

It tied the center of the block together and worked really well! The stock car in the picture ran every weekend for some years and ran upwards of 5000 RPM. Never one single issue, it was built for a very good friend of mine!

Thanks, Gary in N.Y.

P.S. One more item I would certainly look into would be to get the block "extrude-honed", never tried it but I believe it MAY be very useful for chasing HP numbers?? Here's a shot (again) of the "pattern" for the girdle.

[HopRod]

GOSFAST, so do you make those for other people? It looks like the outer bolts are splayed towards the outside of the block. Very neat design!

[GOSFAST]

Originally Posted by HopRod

GOSFAST, so do you make those for other people? It looks like the outer bolts are splayed towards the outside of the block. Very neat design!

Hi "Hop" (do you have a first name maybe), I don't plan making any more of those girdles, if you take the time I'm sure you can either do one OR get a "good" machine shop to fabricate it for you! The couple I did back then were both "hand-made", before we had use of the CNC. Might be a bit easier to do one on the mill now but I can't help at this time!

Here's the issue with "3-lb straps" (kidding of course with the weight) that straddle the main cap, they don't help with supporting one of the weakest areas (in my opinion) of the block, namely the section where the main bolts/studs reside, down below the main cap register? We're talking only the center main, this is where the most "crank-flexing" occurs!

Thanks, Gary in N.Y.

P.S. I would also consider using a 52% bobweight (instead of the more conventional 50%) for a build that would more than likely be run constantly in a higher RPM band? This is just my own opinion here!

[flatheadmurre]

I never use a 4-bolt main on a flathead...either toolsteel 2-bolt main cap with ARP bolts or a wide main cap bolted to the panrail.
Anything drilled into the center mainweb is a startingpoint for a crack and a failure.
And if you´re building a performance motor you want to make sure main bore is perfectly straight...friction and flexing crankshafts is not doing you any good.
The only thing that is certain about bobweight calculation is that there is no consensus among engine builders regarding the benefits of over- or underbalancing a crankshaft...you ask 10 and you get a dozen different answers...

[Pete]

Originally Posted by GOSFAST

P.S. I would also consider using a 52% bobweight (instead of the more conventional 50%) for a build that would more than likely be run constantly in a higher RPM band? This is just my own opinion here[/I][/U]!

That is not just your opinion. Also mine and several builders of 410 sprint car engines. I use 55 though.

[tubman]

Originally Posted by Pete

That is not just your opinion. Also mine and several builders of 410 sprint car engines. I use 55 though.

"GOSFAST" uses 52% and you use 55% and agree with him? Looks like "flatheadmurre" is right again.

[Pete]

Originally Posted by tubman

"GOSFAST" uses 52% and you use 55% and agree with him? Looks like "flatheadmurre" is right again.

I have been doing it since the first time I ran a balancer in 1954. I have never heard of anyone doing destructive testing to find the ideal percentage.
We use 70% for some single cylinder engines.

[KiWinUS]

What balancer do you now use Pete?

[tubman]

Originally Posted by flatheadmurre

The only thing that is certain about bobweight calculation is that there is no consensus among engine builders regarding the benefits of over- or underbalancing a crankshaft...you ask 10 and you get a dozen different answers...

As I said, it looks like "flatheadmurre" is right again.

[Pete]

Originally Posted by KiWinUS

What balancer do you now use Pete?

We have an old Stewart Warner. Have to lift the crank by hand or hoist over to the drill stand. Good upper body exercise.

[Pete]

Originally Posted by tubman

As I said, it looks like "flatheadmurre" is right again.

He may be right but his math is off a couple.......giggle

[KiWinUS]

Thanks Pete
I use. Sunnen.

[GOSFAST]

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Originally Posted by tubman

"GOSFAST" uses 52% and you use 55% and agree with him? Looks like "flatheadmurre" is right again.

Not exactly, on 98% of our builds we use the conventional 50% bobweight formula, the others (all track-only) get anywhere from 52% thru 56%. We have dynoed literally "thousands" of motors (over a 40 year span) and refer back to the dyno sheets for the best results, including the bobweight numbers!

Thanks, Gary in N.Y.

P.S. Being a Flathead is definitely not going to be running at 7000/8000 RPM on the build were talking here I would use the 52% number! I would definitely also do something (like our girdle) to help keep it all together, at least on that "weak" center main area of the block (see the photo below)! I would also add, if Ford didn't "hang" the 2 large center counterweights on each side of the center main on the later units they would never have been able to keep that main brg from disintegrating. The Chevy race cranks have this same setup! Without those counterweights on 4.750" stroke Chev the mains will never survive, been there, tried it!

[Pete]

Originally Posted by GOSFAST

Being a Flathead is definitely not going to be running at 7000/8000 RPM on the build were talking here I would use the 52% number! I would definitely also do something (like our girdle) to help keep it all together, at least on that "weak" center main area of the block (see the photo below)! I would also add, if Ford didn't "hang" the 2 large center counterweights on each side of the center main on the later units they would never have been able to keep that main brg from disintegrating. The Chevy race cranks have this same setup! Without those counterweights on 4.750" stroke Chev the mains will never survive, been there, tried it!

"Being a Flathead is definitely not going to be running at 7000/8000 RPM".

This part of your statement is totally wrong. An all out vintage circle track engine will have the hp peak in the 6500 to 7000 range and will be run 10 to 12 % over that at lift point on the track. That equates to somewhere over 7000 twice a lap. (assuming you are not in traffic)

[Ol' Ron]

It's harsd to imagine getting that much air into a flathead, to mak power at 6 or 7000 rpm. I have allot to learn, But at 87 I sometimes forgrt my name. Now with a Blower, or alittle smack, that;s a different story.
Gramps

[Tim Ayers]

I know he's busy getting ready to head out west to Bonneville, but I'd really like Ronnie Roadster to jump in on the bearing cap support part of the this discussion.

I don't want to misquote him, but I think I recall him saying he only uses a strap support on that he designed on the center cap only on all but the Ardun full race motors.

I be interested to see Gary's 4 bolt set up, but I'm struggling to see how it doesn't compromise the pan rail/center web.

[Fordestes]

Speaking of main support anyone here use the Flatattack support plate with the billet main caps? is that system good, bad, better than nothing ?

[Ronnieroadster]

Hi Tim OK heres one of my simple secret improvements to add strength to our beloved flathead blocks.
Let me explain what I have learned running our flatheads full out not only for records at Bonneville but also for our many dyno pulls. Theres absolutely no need for the massive girdles I have seen many use however if thats what you want to use go for it but it is waste of money,time and weight.

On all of my record setting flathead blocks to add support to the center main bearing cap I simply place a flat steel support the width of the cap and one inch in height on top of the steel center bearing cap this support is bolted to the cap with 5/16 hardware which is only used to locate this support.

The steel support is long so it touches the inside surface of the oil pan. Now heres where the support is made to the center of the block. On the outside of the oil pan theres a steel plate that touches the outside of the pan wall and also has a flat surface sitting on top of the oil pan covering three oil pan bolt holes. This L shaped plate is held in place by the three oil pan bolts on each side of the oil pan.

Now for the additional strength I add a 7/16 cross bolt that now goes threw the steel outer plate and the oil pan side wall and finally threads into the side of the inner steel center main bearing cap support. This assembly adds a huge amount of central support to the block. Think how much effort it will take to move such a structure.

I can tell you we have tested out our design not something I wanted to do but going for records has had its ups and downs. Here goes on the backup run for the record at the 2 1/2 mile marker we experienced a huge internal failure due to oiling issues the two rear connecting rods which were steel Cunningham rods broke after the bearings seized on the rod journal.

The now broken rods number 4 and 8 began chain sawing the inside of the block the steel cam was broken into many pieces between the center and rear cam bearings. With the cam broken the lifters now joined the cam parts hitting the spinning crankshaft slamming into everything possible.
With that much internal carnage the center main bearing area of the block remained completely intact. The crankshaft survived with a slight run-out in the center when I checked it between centers. I will add on more detail all of the internals in this and all my engines are USA products no off shore stuff EVER.


Oh I forgot to add even with this complete disaster on the return run the car coasted across the line over 170 MPH we bumped the record by 20 MPH at that point we now had two records. Now years latter we have set four more records with our flathead engines each one using this simple center main support design.
Ronnieroadster

[KiWinUS]

Ronnie thanks for great explanation & sharing you wealth of knowledge.
Cheers
Tony

[HopRod]

Originally Posted by Ronnieroadster

Hi Tim OK heres one of my simple secret improvements to add strength to our beloved flathead blocks.

On all of my record setting flathead blocks to add support to the center main bearing cap I simply place a flat steel support the width of the cap and one inch in height on top of the steel center bearing cap this support is bolted to the cap with 5/16 hardware which is only used to locate this support.

The steel support is long so it touches the inside surface of the oil pan. Now heres where the support is made to the center of the block. On the outside of the oil pan theres a steel plate that touches the outside of the pan wall and also has a flat surface sitting on top of the oil pan covering three oil pan bolt holes. This L shaped plate is held in place by the three oil pan bolts on each side of the oil pan.

Now for the additional strength I add a 7/16 cross bolt that now goes threw the steel outer plate and the oil pan side wall and finally threads into the side of the inner steel center main bearing cap support. This assembly adds a huge amount of central support to the block. Think how much effort it will take to move such a structure.
Ronnieroadster

Ronnie, so if I understand your design correctly, does tightening the oil pan bolts, via the L shaped bracket, increase preload on the main cap?

[Ronnieroadster]

Originally Posted by HopRod

Ronnie, so if I understand your design correctly, does tightening the oil pan bolts, via the L shaped bracket, increase preload on the main cap?

The oil pan bolts only hold the L shaped support tightly to the oil pan rail surface. Once the bolts are tightened I now drill the cross bolt hole now going threw the L bracket and into the side of the oil pan and finally into the side of the steel support. I use a center drill for this operation. The idea is to get a centered hole location into the side of the main bearing cap support so every time things come apart and go back together the support locates exactly as the first time. Once i have that centered location I now remove the steel support thats on the main bearing cap and finish drilling the needed tap size hole for the 7/16 bolt using the drill press. To keep things accurate every time I do not use an oil pan gasket. I seal the pan to the block using a good quality silicone sealer.
Ronnieroadster

[Lawrie]

Ronnie, you got any pics of that setup?
Lawrie

[Yoyodyne]

Very clever setup, I wouldn't have thought of going through the pan with fasteners.
Do you modify the main cap for a seat for the bar, or just have it bear on the spotface areas for the main bolts? Where are the 5/16 bolts located and how are they used?
I'll never do this to a flathead, but I might be able to apply it elsewhere.

Thanks for the description!

[Tim Ayers]

This is not to sound like a fan boy, but more so as someone who admires mechanical ingenuity and the ability to problem solve. We are fortunate to have a bunch of these guys on this forum who are willing to share their knowledge and experience freely.

Going to Ron's shop and seeing some of his tricks and modifications he does to these engines is truly inspiring.

Standing next to his race car as it starts up and feeling the exhaust literally punch you in the chest is impressive to say the least. Then you hear the sound of the motor...

I feel very fortunate to have gotten to know Ron and his family. When he gives me advice, I listen.

[Pete]

Originally Posted by Tim Ayers

This is not to sound like fan boy, but more so as someone who admires mechanical ingenuity and the ability to problem solve. We are fortunate to have a bunch of these guys on this forum who are willing to share their knowledge and experience freely.

Well, I feel the same way. Ron, JWL, I and others have shared much info by email over the years. I have learned many things from them and I hope I have been of help also. I hope to meet them in person some day.
Vintage racing has been very good to me over the years. Much more so than the pro racing that gave me most of what I know.

One of the most important things I tell vintage RACING engine builders is, follow what the TOP current day pros in ANY racing venue are doing to their engines. Then if it looks like that procedure may help a vintage engine, modify it so as to apply and try it.

[frnkeore]

Is there a cubic limitation in H/Gas? Or a cubic inch to weight rule?

As a basic thing with a N/A, FH, you need as much compress, as you can possibly get.

Make sure you know the compressed thickness of you head gasket, then order your pistons to get .038 +/- .002., piston to head clearance.

The stock deck height is 10.437 +/- .005. To order pistons, you'll have to know that and the depth of the dome in the head, to get things right. The dome varies, in different heads, as you know.

You can use the Ol' Ron method to measure the dome clearance, by wading some tin foil and turning the engine over.

It takes a lot of actual measuring to get max compression out of these engines.

[frnkeore]

Added:
I don't know how after market piston manufacturer's measure CH (I'm to cheap to order a set) but, Ford measures to the corner of the dome, above the top ring, not to the top of the dome. That corner, also has to be more than .036 from the head surface so, make sure you know what that measurement is. Std CH is 1.530, as I remember.

[frnkeore]

One more time

I didn't read the whole 2nd page! I now know that it 11 lb per CI, right?

First a FH will put out more HP per CI, the smaller it's displacement. The ports are the limiting factor, they are only 1.312, in diameter. You can increase the size a with a high level, grinding effort but the middle area is the most difficult and much harder to make consistent. Bigger intake valves won't do much w/o opening that port.

It was mentioned to use 239 CI and 2629 lb so I have a suggestion. I'm building a 21 stud at 3.142 (.080 over) and I'm going to have a 59A crank offset ground to 3.85 stroke, equaling 239 CI. The stoke isn't so much for CI but, much more to increase the CR, using my Victor compressed thickness of .060.

I goes like this:

1/2 stroke = 1.925

Rod = 7.00

CH of piston = 1.53
------------------------
10.455

Block 10.437

Head gasket = .060
--------------------
10.497
-10.455
---------
0.042 piston to head clearance with FT pistons and heads.

You can juggle the dimensions any way you want, such as different head gasket thickness, stroke lengths and CH's But, what ever you do, get that piston as high as you can w/o getting under .036 clearance.

[Ronnieroadster]

Originally Posted by Lawrie

Ronnie, you got any pics of that setup?
Lawrie

Lawrie everything is loaded in the trailer at the moment. When we return from Speedweek I can take some pictures. But it will be a couple of weeks from now.

[Ronnieroadster]

Originally Posted by Yoyodyne

Very clever setup, I wouldn't have thought of going through the pan with fasteners.
Do you modify the main cap for a seat for the bar, or just have it bear on the spotface areas for the main bolts? Where are the 5/16 bolts located and how are they used?
I'll never do this to a flathead, but I might be able to apply it elsewhere.

Thanks for the description!

The support bar sits directly on top of the main bearing cap. The central area of the cap is machine flat this is a rather wide and long area for support. The bearing cap area where the bar sits is machined to a specific height so I can interchange parts between engines if needed. The bar sits high enough to clear the stud, washer and nut assembly's holding the bearing cap to the block. To clear the studs holding the cap in place clearance holes are required in the bar.
Ronnieroadster

[Lawrie]

Thanks Ronnie, hope you have fun at Bonneville, wish we were there.
Lawrie

[Yoyodyne]

Originally Posted by Ronnieroadster

The bar sits high enough to clear the stud, washer and nut assembly's holding the bearing cap to the block. To clear the studs holding the cap in place clearance holes are required in the bar.
Ronnieroadster

Oh I get it, the cap studs don't hold the bar, the bar is above and goes over top of the nuts. I assumed it would be all bolted together by the main studs/bolts. Nice.

I made cap supports sort of like that for 9" ford rears that fit in stock housings before aftermarket cases were plentiful, with through bolts and a flat machined on the cap and .001 squeeze fit.

[frnkeore]

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This question is more for Pete and Kiwi.

I have a high end dyno sim. I had already run it with my above 21 stud info, using a 59A cam. I estimate that I will be able to get at least 9.2 CR out of it so, I changed out the cam to Howards 260 @ .050 x .440 lift cam on a 110 LSA. With that I got 239 hp @ 5400 and 255 lb ft @ 4400. I then advance the cm 5 deg and got, 237 @ 5400 and 258 lb ft @ 4000. Note that the advanced cam, gave 3 more average hp and 4 more average TQ.

The program gives you a flat head block to start with, I added a 1.6 exhaust valve to it but, left the intake alone because it's hard to make improvement with it. Headers where as short as I could make them, to have a realistic exhaust. 14.4 primarys and 3.2 collector. Not ideal, I know.

What do you think about the HP / TQ and rpm levels?

[Pete]

Originally Posted by frnkeore

This question is more for Pete and Kiwi.

I have a high end dyno sim. I had already run it with my above 21 stud info, using a 59A cam. I estimate that I will be able to get at least 9.2 CR out of it so, I changed out the cam to Howards 260 @ .050 x .440 lift cam on a 110 LSA. With that I got 239 hp @ 5400 and 255 lb ft @ 4400. I then advance the cm 5 deg and got, 237 @ 5400 and 258 lb ft @ 4000. Note that the advanced cam, gave 3 more average hp and 4 more average TQ.

The program gives you a flat head block to start with, I added a 1.6 exhaust valve to it but, left the intake alone because it's hard to make improvement with it. Headers where as short as I could make them, to have a realistic exhaust. 14.4 primarys and 3.2 collector. Not ideal, I know.

What do you think about the HP / TQ and rpm levels?

On a 1/4 mile dirt track I would gear it to run from 4000 to 6100.
With a good car, you should be able to flat foot it all the way.

[KiWinUS]

Originally Posted by frnkeore

This question is more for Pete and Kiwi.

I have a high end dyno sim. I had already run it with my above 21 stud info, using a 59A cam. I estimate that I will be able to get at least 9.2 CR out of it so, I changed out the cam to Howards 260 @ .050 x .440 lift cam on a 110 LSA. With that I got 239 hp @ 5400 and 255 lb ft @ 4400. I then advance the cm 5 deg and got, 237 @ 5400 and 258 lb ft @ 4000. Note that the advanced cam, gave 3 more average hp and 4 more average TQ.

The program gives you a flat head block to start with, I added a 1.6 exhaust valve to it but, left the intake alone because it's hard to make improvement with it. Headers where as short as I could make them, to have a realistic exhaust. 14.4 primarys and 3.2 collector. Not ideal, I know.

What do you think about the HP / TQ and rpm levels?

Interesting but I believe those numbers are light years off. As Pete has eluded to numerous times the flathead can be organized to make good power but it comes at a large cost. Your simulated engine sounds like just a home built hot rod engine. The engines my boss built several of for the great American race were expensive 3.5/16 x 4.250 ported balanced good rods 1.6 valves great ignition single 48 Stromberg with phenolic spacer. Very detailed internally. 145hp. 2 carbs 165hp real dyno numbers. The stainless headers on his 40 coupe with this engine & been in TGAR. are spectacular looking. I have driven this car @ 110mph & still pulling strong. Electronic corrected speedo for race. It will pul from 30 mph in high gear but at 65 mph it sits you back in seat & throbs. These are ligit dyno numbers at crank. Not “happy dyno numbers” now these engines could drive across the great USA & back several times with zero issues.
Cheers
Tony

[Tim Ayers]

Originally Posted by KiWinUS

Interesting but I believe those numbers are light years off. As Pete has eluded to numerous times the flathead can be organized to make good power but it comes at a large cost. Your simulated engine sounds like just a home built hot rod engine. The engines my boss built several of for the great American race were expensive 3.5/16 x 4.250 ported balanced good rods 1.6 valves great ignition single 48 Stromberg with phenolic spacer. Very detailed internally. 145hp. 2 carbs 165hp real dyno numbers. The stainless headers on his 40 coupe with this engine & been in TGAR. are spectacular looking. I have driven this car @ 110mph & still pulling strong. Electronic corrected speedo for race. It will pul from 30 mph in high gear but at 65 mph it sits you back in seat & throbs. These are ligit dyno numbers at crank. Not “happy dyno numbers” now these engines could drive across the great USA & back several times with zero issues.
Cheers
Tony

I'm with you on this, Tony. Those numbers seem really optimistic. There is book written by George Nichols (I believe) and he uses a similar dyno program. Every cam he put into the program had the motor making 200+ hp.

I would check the specs on the Howard cam as well. Potvin Eliminator was at .425" and that is pretty radical cam. Howard's were not known for making radical stuff like Potvin. Crane or Isky's 404A.

Many of the builders on this site would be doing back flips if it was that easy to make those numbers.

[KiWinUS]

Thanks Tim. Besides my KiWi-L100 I have a Potvin Eliminator master so can grind & I Have original 404A NOS & nice used but with these sweet cam plus others in my collection ( we all know there’s way more to this than cams. These numbers are. To put it nicely Interesting.

[Pete]

Today's trivia lesson.

Howard Johanson (Howard's Cam's) was a neat guy that drank beer from quart bottles.

[frnkeore]

I forgot to add to my specs, that it had 3, 165 carbs (495 cfm @ 3" Hg).

I'm not so interested in the actual HP, but, more the peak rpm, for both hp and tq, as well as what the 5 deg advance does, to the average hp & tq.

Tim, the cam lobe specs are accurate. It's Howards top duration and lift profile for the FH. The lift and duration, is a product of lifter diameter and the maximum lift velocity for that size lifter. SBC, .842 lifters, lift velocity, isn't even in the same universe as a 1" flat heads lifter. If you were to use these Howards FH cam profiles, with a 1.6, or greater rocker arm, you have valve events, that will beat some roller cam profiles.

[Pete]

Originally Posted by frnkeore

I forgot to add to my specs, that it had 3, 165 carbs (495 cfm @ 3" Hg).

I'm not so interested in the actual HP, but, more the peak rpm, for both hp and tq, as well as what the 5 deg advance does, to the average hp & tq.

Tim, the cam lobe specs are accurate. It's Howards top duration and lift profile for the FH. The lift and duration, is a product of lifter diameter and the maximum lift velocity for that size lifter. SBC, .842 lifters, lift velocity, isn't even in the same universe as a 1" flat heads lifter. If you were to use these Howards FH cam profiles, with a 1.6, or greater rocker arm, you have valve events, that will beat some roller cam profiles.

Frank,
The lift figures of that Howard cam are very similar to ones used by the DO Hal for mile track events.

[frnkeore]

As I said, I'm not building that engine. It was just food for thought, regarding what could be done with a smaller cube (higher hp per CI) engine, in a light car.

I just added the cam profile and 3 carbs, to my high compression 239 CI, 21 stud engine.

This is what it predicted my 239, single carb (165 cfm), 9.2 CR engine, 1.6 ex valve would do, with a 59A cam. I don't think it's to far out of line for the CI & CR.

What would you expect form a 9.2 CR 59A, with a larger ex valve?

[Ldjr003]

If you 're talking about ANY cast crank, I would steer real clear ! What's wrong with the Mercury 4" crank. Nothing ! ! It is a superior piece. Rods.... Ford 8BA rods, polish side beams, have them resized, new bushings. These factory rods are a lot stronger than folks give them credit for. Best of luck. I 'mdown here in South Carolina, be looking for your car inthe near future !

[Ldjr003]

You can purchase a very simple main cap support from Speedway Motors, I'd also install ARP rod nutz too. Install a cam with at least 400" lift, Isky 4 00Jr. or Potvin 425 are some good choice. Ues, relieve the block about 100 thousanths of an inch, install Chevy race type valves, 1.60" intales and 1 .50" exhausts. And first and foremost, check for cracks in your block, especially around mains to block, and valve to bore.

[Ldjr003]

What !!!!! Unless you can machine off a good chunk from your heads, that'sthe only way to gain more compression on a Flathead. The pistons ARE what gives you the compression. And most off the shelf heads, including Edelbrocks, will only get you about 9.5 to 1, with a slightly domed pistons. Flat tops might give ya, uhhhhhhh, 6 to 1.

[Ldjr003]

Maybe Ohio Cramkshaft, Speed O Motive used to be good, I think they are gone ???? With all thoseshops in NC, nobody can take a Merc 4" crank andstroke to 4 1 /8 th. Scats forged steel cranks are really expensive, and I would run away from any cast crank, dont care whos name is on the box.

[Pete]

Originally Posted by Ldjr003

What !!!!! Unless you can machine off a good chunk from your heads, that'sthe only way to gain more compression on a Flathead. The pistons ARE what gives you the compression. And most off the shelf heads, including Edelbrocks, will only get you about 9.5 to 1, with a slightly domed pistons. Flat tops might give ya, uhhhhhhh, 6 to 1.

Flat tops give us 14 to 1.

[Lawrie]

Where not the stock ford cranks cast?
Lawrie

[frnkeore]

The Highest compress you can get, on one of these engines, will be with FT pistons, with a CH or stroke set to get your piston within .042-.038 (possibly .036) of the head.

Even getting a dome head up to that clearance, will be a little less, because the dome shape, has more area than a flat. The transfer area shape, also will make a difference to the CR. The difference of how high the top rings is, also has a minor effect, as well as how thick the valve margin is.

Also, after posting my sim HP/TQ estimate, I asked around, on different sites, to find flow numbers on our engines. I found flow bench numbers, The guy, cut up a block, to mount on his bench and ported and installed 1.6" valves but, I only got the intake flow and I estimated the exhaust at a few cfm less, although I think the exhaust will flow more.

Anyway here are my revised numbers and what this flow looks like when added to the program.

Again, it's 239, 9.2 CR FT piston .038 head clearance, 1 carb on the stock cam and 3 x 165 cfm on the big cam.

In think the stock cam sim HP, is believable, take the 262 @ .050 cam, with .440 lift -.012 at what ever you want, it a pretty radical cam!

I would like a opinion, if possible, on the accuracy of peak rpm (5400) with that cam. The valve events are:

Lobe Lift .010--.020--.050--.200-- Max lift- .440
Duration 315.9-286.8- 262--189.5

[Ol' Ron]

The actual compression an engine sees is after the intake closes. It's called "dynamic CR" and is a good reason Long duration cams don't have allot of torque at low RPMs. The volume of the combustion chamber determinees the "Static CR". This includes the area over the valves. High lift cams need a place to put the valves when they open. Remember Horsepower needs air to make HP amd the combustion chamber is part of the intake port when it has to provide the AF to reach the piston. With all the Mathematical skills of our readers, determine the chamber volum you need to make 12:1 cR in a 276 engine, now a 350 ci.. This is the reason blowers make allot of HP

[Ol' Ron]

Mtt

[Ldjr003]

Mercury cranks were Nodular Iron, or Forged Steel.

[Ldjr003]

Yeah right.

[Ldjr003]

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14 to 1 CR on a Flathead ??? Dream on pal. Show us how you did it if it's true, which it ain't. Even if you welded the combustion chamber, the valves still have to have somewhere to go at cam lift. And if you welded all around the valves in the head, that motor wouldn' t breath work a s..., and it would'nt make enough power to fall off a curb.

[Pete]

Originally Posted by Ldjr003

Mercury cranks were Nodular Iron, or Forged Steel.

There were never any forged flathead cranks.
The steel Mercury ones were shell molded

[Pete]

Originally Posted by Ldjr003

14 to 1 CR on a Flathead ??? Dream on pal. Show us how you did it if it's true, which it ain't. Even if you welded the combustion chamber, the valves still have to have somewhere to go at cam lift. And if you welded all around the valves in the head, that motor wouldn' t breath work a s..., and it would'nt make enough power to fall off a curb.

Ah, another expert has come aboard. Welcome.
It is common practice when a new poster comes on to introduce and tell a bit about yourself.

By the way, 14 to 1 or more has been quite possible since the early 50's.
The names, Smokey Yunick and Speedy Spiers and myself come to mind.

[Ol' Ron]

I used a mockup combustion chamber with a wedge piston and cylinder head made from wood the areary over the piston had an 8 deg angle and the piston a 7 degree angle. This allowed for exelent flow and a very hi compressio,
Several years later at Bivlle I saw an engine tare down for inspection with the same chamber. I had contacted Egge to mmake a set of pistons for me, but the cost was more than I could afford. But somebody thought it was a good idea.

[Ldjr003]

Then tell us how ! Even that kind of cr on an OHV motor would be real hard to find high enough octane to run it without it detonating itself into little pieces. Show us all the proof. Oh, by the way, I have HotRod magazines going back to the late 1940s. If someone has achieved 14.2 on a Flathead, it'll be in there somewhere.

[KiWinUS]

Smokey. That’s the guy that could not get the new Chevy Rat engine to make good power & live so Chevrolet had Smokey send the engine to Jr Johnson where a young Robert Yates’s was moonlighting after he got off from his day job at Holman & Moody. Robert made the big block scream with HP & survive. I will stop at that for now as the rest is history.
Cheers
Tony

[Pete]

Originally Posted by Ldjr003

Then tell us how ! Even that kind of cr on an OHV motor would be real hard to find high enough octane to run it without it detonating itself into little pieces. Show us all the proof. Oh, by the way, I have HotRod magazines going back to the late 1940s. If someone has achieved 14.2 on a Flathead, it'll be in there somewhere.

These are race engines. We run alcohol.
I do have one customer that runs 118 race gas and it works fine.

I seriously doubt you will find any useful information on advanced engine development in Hot Rod Magazine.

As far as telling the World what goes into one of my engines other than what has already been talked about, that is not going to happen in this lifetime.
In the next lifetime, I will teach anyone all I know as long as they have an IQ equal to or higher than their age.

[Pete]

Originally Posted by KiWinUS

Smokey. That’s the guy that could not get the new Chevy Rat engine to make good power & live so Chevrolet had Smokey send the engine to Jr Johnson where a young Robert Yates’s was moonlighting after he got off from his day job at Holman & Moody. Robert made the big block scream with HP & survive. I will stop at that for now as the rest is history.
Cheers
Tony

Yes, you are right. I was refering to Smokey and the Hudsons. I quit following NASCAR after that.

[Ol' Ron]

Getting 14:1 CR is difficult, but not impossible. Especially with a large displacement block. However getting any HP from it would be limited by the amount of air you could get into it. Alky is not a great fuel and you need twice as much by volume to equal any gas. Now with alittle Nitro, that's another story.. Oxygen is the key to horsepower. Yne more you have, the more power you get.

[Tim Ayers]

Originally Posted by Ol' Ron

Getting 14:1 CR is difficult, but not impossible. Especially with a large displacement block. However getting any HP from it would be limited by the amount of air you could get into it. Alky is not a great fuel and you need twice as much by volume to equal any gas. Now with alittle Nitro, that's another story.. Oxygen is the key to horsepower. Yne more you have, the more power you get.

Interesting. Yes, I have some alky Stromberg jets that are huge!

[Pete]

Originally Posted by Ol' Ron

Getting 14:1 CR is difficult, but not impossible. Especially with a large displacement block. However getting any HP from it would be limited by the amount of air you could get into it. Alky is not a great fuel and you need twice as much by volume to equal any gas. Now with alittle Nitro, that's another story.. Oxygen is the key to horsepower. Yne more you have, the more power you get.

Conversion from race gas to straight alcohol is good for at least 10% increase in hp. assuming optimum tune for each.

[Tim Ayers]

Originally Posted by Pete

Conversion from race gas to straight alcohol is good for at least 10% increase in hp. assuming optimum tune for each.

Pete,

How much of jump does that 10% represent in your typical race motors? Are we talking another 20-30 hp just from fuel & tune?

[Pete]

Originally Posted by Tim Ayers

Pete,

How much of jump does that 10% represent in your typical race motors? Are we talking another 20-30 hp just from fuel & tune?

I don't know. I haven't poured any gas in one since the 50's except down the injectors to start.

[old Tom]

They used to say that running straight alcohol let the engine run cooler. I don't know how much that would help in drag racing but I am sure it was a factor in stock car racing.

[Tim Ayers]

Originally Posted by old Tom

They used to say that running straight alcohol let the engine run cooler. I don't know how much that would help in drag racing but I am sure it was a factor in stock car racing.

For exactly this reason, in the 90's someone sold alky-only racing heads that had no water outlets or jackets. They were a billet slab and the customer could choose their own compression ratio. I'll try to find the info on these.

[Ol' Ron]

This discussion, has not solved the problem of getting air into the engineMost stock engines of 4.2/5.0 liter engines produce more power than a highly modified fathead. WHY???? they get more air.

[Tim Ayers]

Originally Posted by Ol' Ron

This discussion, has not solved the problem of getting air into the engineMost stock engines of 4.2/5.0 liter engines produce more power than a highly modified fathead. WHY???? they get more air.

In thinking of this, would a Smith-type "jiggler" head that placed the intake valve over the piston to allow for a higher lift/larger valve in order to get more air into the motor help?

[Ol' Ron]

Arduns work very well.

[frnkeore]

Originally Posted by Ol' Ron

This discussion, has not solved the problem of getting air into the engine. Most stock engines of 4.2/5.0 liter engines produce more power than a highly modified fathead. WHY???? they get more air.

So then, the best way to fill that cylinder, with the port that came with these engines, is to reduce the cubic inch displacement, to get the highest HP per CI.

In a class that has 11 lb per CI, it would make since to reduce the size of the engine or, at least increase it to a minium and get as much compression as possible.

A .030 over 221, 24 stud, would be a 225 with the stock stroke and 217.75 if you offset grind it to 3.625. A 239 would be 243.85 and 235.7 with the 3.625 stroke. With the smaller engines, porting and as much compression as possible, I think you could get 1 HP per CI, or more.

I can't tell you what it might take to get 10/1, or higher C/R on a engine that small but, that means that you can have a car as light as 2398 lb.

[Tim Ayers]

Originally Posted by Ol' Ron

Arduns work very well.

Haha. Yes they do. My Smith "jiggler" suggestion was in the spirit of keeping it a flathead.

In all my travels, I only saw one pair of Smith Jigglers and it was at Hershey. It was in the late 90's. If only I had a time machine.

[Tim Ayers]

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Originally Posted by frnkeore

So then, the best way to fill that cylinder, with the port that came with these engines, is to reduce the cubic inch displacement, to get the highest HP per CI.

In a class that has 11 lb per CI, it would make since to reduce the size of the engine or, at least increase it to a minium and get as much compression as possible.

A .030 over 221, 24 stud, would be a 225 with the stock stroke and 217.75 if you offset grind it to 3.625. A 239 would be 243.85 and 235.7 with the 3.625 stroke. With the smaller engines, porting and as much compression as possible, I think you could get 1 HP per CI, or more.

I can't tell you what it might take to get 10/1, or higher C/R on a engine that small but, that means that you can have a car as light as 2398 lb.

You may be interested to read about Barney Navarro's work with small displacement flatheads. He de-stroked some of his blown engines to fit into different race classes, but I believe he also understood the need to get more air into the motor. Between oxygen injection and blowers, I think Barney was on the right track.

[tubman]

With all of this talk about getting more air (oxygen) into these engines, I have to wonder why Nitrous Oxide is not more popular.

[Ldjr003]

Yeah OK, and I bet you have a 307 in a 69 Nova with a Powerglide, 3.23 gears, single 4v, that runs 9's in the quarter, through the mufflers, on street tires, with no power adders !

[Tim Ayers]

Originally Posted by Ldjr003

Yeah OK, and I bet you have a 307 in a 69 Nova with a Powerglide, 3.23 gears, single 4v, that runs 9's in the quarter, through the mufflers, on street tires, with no power adders !

How are you talking to? Why are you being so negative?

[tubman]

I have to keep reminding myself, don't pick on the easy ones.

[Tim Ayers]

Originally Posted by tubman

I have to keep reminding myself, don't pick on the easy ones.

Haha. Good advice.

[Ol' Ron]

In jWL book, the first 100 pages discribe the modification of a stock engine, without going into it. He never got a 100 HP from it. but, the original engine ony produced 80 HP. Something to think about.

[old Tom]

would a GMC 371 blower give it more air

[KiWinUS]

Yes Sir Tom.

[petehoovie]

Originally Posted by old Tom

would a GMC 371 blower give it more air

[JSeery]

Ok, we are talking about building an engine for a specific racing class. All of these ideas that are outside of the class restrictions are not going to help! And 1 hp/ci is not easy to comeby on a NA flathead on gas. We are talking some big bucks.

[Yoyodyne]

Did Ford ever state a reason for the change to domed pistons and chambers, or announce a claimed benefit? I've wondered this since starting to investigate 21 stud engines.

[Tim Ayers]

Originally Posted by old Tom

would a GMC 371 blower give it more air

Not sure why, but 4-71 seems to work better for the snouts are easier to come by. A 3-71 snout that works for a flathead is like hen's teeth.

[petehoovie]

Originally Posted by Tim Ayers

Not sure why, but 4-71 seems to work better for the snouts are easier to come by. A 3-71 snout that works for a flathead is like hen's teeth.

From the H.A.M.B. > https://www.jalopyjournal.com/forum/...1040241/page-2

[frnkeore]

Food for though.....

HP costs money but HP per CI, can cost a lot more. HP per CI, is what wins races in class racing.

Now a days, you can easily build a 304 to as much as a 315 CI FH, using the 4.25 cranks. But, because of the little 1.312 ID intake port, each time you go up, in CI, you gain total HP but, loose HP per CI. Even with a blower, you can't get much threw that port. I would bet a Built, N/A 302 SBF will put out more than a blown FH of the same CI.

You gain some on C/R as you increase CI but, you loose breathing ability. For the street, CI helps and blowers help but, you'll never win a class race that way.

The old saying "speed costs money, how fast do you want to go?" will always apply, especially in class racing.

[Tim Ayers]

Originally Posted by frnkeore

Food for though.....

HP costs money but HP per CI, can cost a lot more. HP per CI, is what wins races in class racing.

Now a days, you can easily build a 304 to as much as a 315 CI FH, using the 4.25 cranks. But, because of the little 1.312 ID intake port, each time you go up, in CI, you gain total HP but, loose HP per CI. Even with a blower, you can't get much threw that port. I would bet a Built, N/A 302 SBF will put out more than a blown FH of the same CI.

You gain some on C/R as you increase CI but, you loose breathing ability. For the street, CI helps and blowers help but, you'll never win a class race that way.

The old saying "speed costs money, how fast do you want to go?" will always apply, especially in class racing.

Not sure you could even make the comparison between a SBF and a normally aspirated flathead. Two different animals.

[Ldjr003]

Originally Posted by Tim Ayers

How are you talking to? Why are you being so negative?

Sorry my messages are being put in the wrong place. I was responding to someone on here who goes by Pete, andI was calling him out about his ridiculous comments about his 14 to 1 compression Flathead making 352 c.i. There is a whole new generation out there getting into Flatheads, and I hate to see them getting useless and untrue information. This will be my 3rd Flathead build, and I've done so much reading and research over the years, NOT from some Dude on Youu Tube or a website such as the Ford Barn. No, I'm not saying there's not useful information on here, I'm saying there's some people out there that , shall I say, don't know what they are talking about. , and thereare other real engine builders, who have done Flathead builds over and over, with real world results. I don't just throw information put there based on what some guy that knows a guy, that knew a guy..... and the 307 , 69 Nova was supposed to be a joke.I've met enough of them. I have Time Slips for the cars /motors I've built, not just hearsay. So......there you have it. I bet Ol' Pete has some ocean front property in Arizona too.....

[Zeke3]

[QUOTE=Ldjr003;1917542]I was responding to someone on here who goes by Pete, [QUOTE]

I think you are picking a fight with the wrong guy. I respect Pete's information regarding building and racing flathead engines.

[HopRod]

As the original post-er of this thread, I too respect Pete's info and knowledge. Pretty sure he has built more than 3 flatheads.

[Lanny]

Ldjr003, suppose I tell you there is a fellow here in MN. that has
built a few Ford Flatheads too, His name is Rick Schnell, and he
built a Ford Flathead dragster that has dynoed at 939hp on 60%
60% Nitromethane fuel. It has the world record of being the quickest
single engine flathead dragster in the world.
Here is a link to a test run he made at BIR, Brainerd, MN. Raceway.

http://myflatheadford.com/worlds-qui...head-dragster/



.

[frnkeore]

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Originally Posted by Tim Ayers

Not sure you could even make the comparison between a SBF and a normally aspirated flathead. Two different animals.

High Tim,
Please take another look at what I said.


I said that a N/A SBF can put out more than a supercharged flathead.

I learned ibefore the end of HS (1962) that the flathead wasn't competitive, with OHV V8's.

[Fordestes]

Originally Posted by Ldjr003

Sorry my messages are being put in the wrong place. I was responding to someone on here who goes by Pete, andI was calling him out about his ridiculous comments about his 14 to 1 compression Flathead making 352 c.i. There is a whole new generation out there getting into Flatheads, and I hate to see them getting useless and untrue information. This will be my 3rd Flathead build, and I've done so much reading and research over the years, NOT from some Dude on Youu Tube or a website such as the Ford Barn. No, I'm not saying there's not useful information on here, I'm saying there's some people out there that , shall I say, don't know what they are talking about. , and thereare other real engine builders, who have done Flathead builds over and over, with real world results. I don't just throw information put there based on what some guy that knows a guy, that knew a guy..... and the 307 , 69 Nova was supposed to be a joke.I've met enough of them. I have Time Slips for the cars /motors I've built, not just hearsay. So......there you have it. I bet Ol' Pete has some ocean front property in Arizona too.....

Mabe the engine started out as a 337 c.i. ? I ran some 337s back in the early 70s they are heavy but can be strong runners for sure.

[Ol' Ron]

ack in the dat, C&T automotive sold stroker kits for allot of engines for the flatheads there were two that were very popular 3/8 x 3/8 296ci and 3/8 x 5/16 284 ci. The cost was $195 I also ran a "Y" block 342?? not sure , but close. Never had any problems with any of them. They all came complete. Rings anrods and bearings. The "Y" block had converted the rods to full floaters. Interesting projects, learning by my mistakes.

[Tim Ayers]

Originally Posted by frnkeore

High Tim,
Please take another look at what I said.


I said that a N/A SBF can put out more than a supercharged flathead.

I learned ibefore the end of HS (1962) that the flathead wasn't competitive, with OHV V8's.

Ah, my error then. Sorry about that.

[Ldjr003]

Originally Posted by Lawrie

Where not the stock ford cranks cast?
Lawrie

Nodular Iron, some Mercury Cranks were Forged Steel.

[Ldjr003]

Originally Posted by Lanny

Ldjr003, suppose I tell you there is a fellow here in MN. that has
built a few Ford Flatheads too, His name is Rick Schnell, and he
built a Ford Flathead dragster that has dynoed at 939hp on 60%
60% Nitromethane fuel. It has the world record of being the quickest
single engine flathead dragster in the world.
Here is a link to a test run he made at BIR, Brainerd, MN. Raceway.

http://myflatheadford.com/worlds-qui...head-dragster/



.

I'm not disagreeing about that Nitro burning Flathead. Awesome machine. I' m just disagreeing with Mr. Pete.

[40 Deluxe]

Originally Posted by tubman

With all of this talk about getting more air (oxygen) into these engines, I have to wonder why Nitrous Oxide is not more popular.

This reminds me of a quote in a magazine many years ago: With nitrous oxide you have a tendency to drive over your own crankshaft!

[old Tom]

those must be the heads hat Tim was talking about.

[old Tom]

Originally Posted by Fordestes

Mabe the engine started out as a 337 c.i. ? I ran some 337s back in the early 70s they are heavy but can be strong runners for sure.

You take a 59AB block and bore it out to the water jackets then sleeve it and bore it to 3,5". Use a 4.5 crank and see how many ci you come up with. back in the day we did not have all the modern technology and material but we still did things.

[old Tom]

You take a 59AB block and bore it out to the water jackets then sleeve it and bore it to 3,5". Use a 4.5 crank and see how many ci you come up with. back in the day we did not have all the modern technology and material but we still did things.

[cadillac512]

346 cu. in.

[Yoyodyne]

I had real hopes for this thread, that ship has sailed.

[Ol' Ron]

Ain't that the truth!!

[frnkeore]

Originally Posted by 40 Deluxe

This reminds me of a quote in a magazine many years ago: With nitrous oxide you have a tendency to drive over your own crankshaft!

I like!

[Lanny]

If set up right, nitrous oxide is a great power maker for short bursts of speed.






..

[jrvariel48]

How about methanol injection?

[HopRod]

Let's get this back on track... We're talking Flatheads here and looking for info/advice that pertains to them.

The engine has to be naturally aspirated. I will be using the Stromberg 250's.
I will be using SCAT H-beam rods.
Ross forged pistons with metric ring pack and undetermined CH pin location.
Edelbrock 1115 heads, this has been cleared with SEGA rules.
Cubic inches have yet to be determined.
Lots of porting in the block is to be expected.

I understand that a smaller engine can produce more HP per CI, but I need HP and torque to get to the end quickly. Bigger engine should do that better, right?

Nevermind the class limits of H/Gas, let's just think vintage drag racing to keep this going.

[Yoyodyne]

Are you limited to the 3-2s, or can you run injection, or a 4 bbl?

[JSeery]

JWLs book might be very helpful. Lots of dyno results per modification.

[frnkeore]

I understand that a smaller engine can produce more HP per CI, but I need HP and torque to get to the end quickly. Bigger engine should do that better, right?

All other things equal, the answer is no.

It is HP per lb, that allows greater acceleration. If you were talking about just, top speed, like Bonneville or even, the standing mile, you might have a point.

The winner at the drag strip, is who gets there first and not the trap speed. Many races are lost, even though the the loosing cars trap speed is greater. The trap speed, is a indicator of actual HP.

In drag racing, the areas you need to work on are traction and using ALL the HP you have, just before getting to the line. That means gearing and gearing also, helps traction, it allows you to run a wider or, taller tire. So, you gear it to turn, slightly over your max rpm, at the line, in what ever the highest gear is, in the trans. Weight distribution, also will help, meaning not just the battery in the trunk but, everything mount as far back as you can get it.

If you just want to have fun, it doesn't make any difference. Just build your engine, to what you want and add the weight that it takes to stay in the class.

[frnkeore]

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On the carbureation end of it, hook up a vacuum gauge and test the vacuum at WOT, in your torque range (Hardest pulling) and if you have more than 1.5" of vacuum (you need bigger carbs) or less than .5" (you need smaller carbs) and you need to keep the A/F ratio, as close to 12.5, as you can.

[tubman]

You don't need a huge engine. There was a guy on here ("MTFlat"?) that ran a steel '32 3-window with an injected flathead that ran consistently in the 13's and occasionally dipped into the 12's. As I remember, his engine was in the 260-270 ci range.

[40 Deluxe]

For drag racing you do not need to worry about what class you fit in! Just go bracket racing. No rules to meet except safety requirements. No worries about running against any cowardly cheaters. No teardowns. Just do a few time trials, put your dial-in on the window and go racing! Your 15 second flathead can win over a 11 second Corvette if you can drive good enough. Quick reaction times and consistency win races, not ultimate HP.

[JSeery]

Originally Posted by 40 Deluxe

For drag racing you do not need to worry about what class you fit in! Just go bracket racing. No rules to meet except safety requirements. No worries about running against any cowardly cheaters. No teardowns. Just do a few time trials, put your dial-in on the window and go racing! Your 15 second flathead can win over a 11 second Corvette if you can drive good enough. Quick reaction times and consistency win races, not ultimate HP.

I did a little bracket racing, didn't like it at all. Different strokes for different folks I guess.

[tubman]

I quit drag racing when they eliminated the human flagman and went to the "Lights".

[JSeery]

Originally Posted by tubman

I quit drag racing when they eliminated the human flagman and went to the "Lights".

Another problem!

[old Tom]

Would a Norden 189 degree crank with a smaller ci engine be competitive?

[frnkeore]

You mean a 180 deg crank, right?

Yes, I think it would and 180's are good with 3 mains. I think that is what the Novi used.

It's said that they have vibration issues but, I don't think it would effect the flathead range of rpm.

[old Tom]

Yes and thank you.

[frnkeore]

Although not early Ford, this is a good example of what HP to weight, can do for you:

https://www.youtube.com/watch?time_c...ature=emb_logo

That little 4th place car, is a Ford Cortina. Those cars had 97 CI engines and weigh about 2000 lb it will have, at least 160 HP but, no more than 190. You can see that he stays right with them.