Which cam to use?

[tubman]

Over the next year, I plan on building 2 engines. One will be a 258 Inch (3 3/4 X 3 5/16) 8BA and the other a 276 Inch (4 x 3 5/16) '51 Merc. The first engine will go into an 1800 lb. "T" touring hot rod, while I plan on putting the larger engine in my mostly stock '51 club coupe. Both engines will have the ports cleaned up, and will be running either 4 BBL carbs (I have a Rochester from a '53 Olds and a WCFB from a '54 Chrysler) or dual carbs on an Offenhauser super dual. (I also have a rebuilt 2GC on an aluminum Mercury manifold I may want to try.) I have an old "flattop" Mallory for the "T" and am supposed to be getting a "Bubba-ized" SBC Mallory to use on the '51. I also have 2 sets of Edmunds head and a new set of Offenhausers. As you can probably see, I have been collecting parts for a looong time, which is the root of my problem.

Basically, I have all the major parts I need to build these two engines with one exception; I only have one cam, an Iskendarian Max-1. I am leaning towards using this in the 276" engine, and getting an L-100 for the smaller engine in the light car. In the mix is that the Mercury is a good runner and the cam and lifters in it seem to be in good shape. IIRC, the Mercury cam is better than a Ford cam, and may be good in a heavy car.

My goal is for both cars to be good street drivers, with performance in mind, but not foremost. Any comments and suggestions will be greatly appreciated.

[40cpe]

deleted, wrong post

[Ol' Ron]

Well I could comment on the cams but won't, right now. The heads may be an issue. Edmunds have a small combustion chamber to give 8:1 on a stock 239 and 8.5 on the Merc.. You might want to cc the chambers. Plus the lift of the L-100 will require the heads to be clearanced. And these are very thin. Don't care for the Mallory either.

[Kahuna]

Hi tub
What is the gear ratio in the axle?
Does the car have an overdrive?

[tubman]

Originally Posted by Kahuna

Hi tub
What is the gear ratio in the axle?
Does the car have an overdrive?

Both cars have 3.55 '49-'51 Ford rear ends. The transmission in the Tub is an overdrive ('50 Ford), while the '51 is not. I do have an complete overdrive setup for for the '51 though.

Ol' Ron : I was intending to run the Offenhauser heads on the 276" engine. I used these same kind of heads on a 276 Merc (with a Max-1) I had in my '36 20 years ago, and they worked fine. I was going to use the Edmunds on the smaller engine. The Flattop Mallory has been completely gone through by Bubba and is going on the small engine, mainly for the way it looks. As to the L100, I'd rather use a milder cam than do major modifications to the heads.

[KiWinUS]

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Tubman , you may have to do a lil clearancing to your heads but I believe you will not find a cam you are more happy with than KiWi-L100's in both engines for both cars even as diverse as the cars are !!!
Cheers
Tony

[JWL]

First, be sure about what you REALLY want in a cam. Next, remember most drivers can adapt to nearly any characteristic offered by a cam. And, once the cam is in there it is difficult for the average human to acknowledge a mistake usually by saying something like "has a great sound" or "easy to drive with". Opinions will run all over the place. Cams that I wouldn't lay a board on and use to roll a heavy item across the shop floor will be touted as wonderful items by some owners. The "BEST" cam for each application depends on completely disclosed application requirements. Simple.

You can get some good info by looking at the Tilden site.

[flatheadmurre]

While your at it why not use a bigger intake valve if your gonna port it anyway.
The Merc cam aint a bad one for a driver.

[scooder]

John,
The mild delong grind in your 276 in your book, that looks like a real nice street grind from the torque curve (ok slightly curved) numbers you got.
What grind is this?
Martin.

[tubman]

Originally Posted by JWL

First, be sure about what you REALLY want in a cam. Next, remember most drivers can adapt to nearly any characteristic offered by a cam. And, once the cam is in there it is difficult for the average human to acknowledge a mistake usually by saying something like "has a great sound" or "easy to drive with". Opinions will run all over the place. Cams that I wouldn't lay a board on and use to roll a heavy item across the shop floor will be touted as wonderful items by some owners. The "BEST" cam for each application depends on completely disclosed application requirements. Simple.

You can get some good info by looking at the Tilden site.

This is what I am trying to do with this post. I have given the types of cars (so you know the approximate weight), the other engine components I am planning on using, my expectations (driveability over power), and even drivetrain characteristics. What have I missed? I'll try to supply it. At 73, I can't afford to be experimenting with various cams and thought I could rely on advice from some folks on here that have been "through the wars".

As further example of where I am on this would be my answer to "Mauritz" : "Given what I know about the cost/benefit of larger valves, I don't think I would even consider going that route for either of these engines, as I am only going to do minor cleanup and portmatch."

[JWL]

What you are missing is that YOU have to make your own decision. Too many times we have seen claims of outstanding performance from one cam or another that has actually been terrible under measured tests. Some opinions matter but none of them count when the decision is yours. Already you have seen advertising in this thread for a cam I couldn't recommend for your stated requirements. The fact is the Ford guys spent mucho time and money developing the best cams for average driving conditions. If there was a way to jack up the power output without making sacrifices somewhere within the "driving range" it probably would have been implemented.

If low end power, similar to the stock examples, is important choose a cam with timing numbers closer to "stock". If you don't mind giving up low end power for a salty idle and higher RPM power then stretch the timing numbers to earlier and later. When you get right down to the bottom line even a very radical roller cam can be driven on the street. I don't like the characteristics of such a cam for my daily drive to lunch but there are those who do.

[Kahuna]

I think JWL has got it right.
Given the weight of your 51 and the axle ratio, something mild might be in order.
I'm a fan of big cams, but as John said, it depends on you and your driving habits
and goals.
I wouldn't hesitate to use one of those L100's or larger cams in a light car with a lower rear end ratio, but there are trade-offs to be aware of.
Actually, I'd use an L100 in the 51 you have now, but that's just me

[JSeery]

The 3:55 rear end gearing will not help even with a stock cam, so any reduction in low end torque is going to hurt acceleration. Add a heavy car and there you go. Cams need gears (IMHO) and acceleration needs gears and light weight. Most cams are basically shifting the torque curve to the right (and up), so without an increase in RPMs you are not going to recover the lost low end torque. It is hard to drive a heavy car with high gearing at increased RPM.

Now, if you just want the sound, that's a whole different matter (and are willing to give up the performance to get it!).

[lonewolf]

107B in the big car

[scooder]

Did you mean 1007B?
Martin.

[deucemac]

For a long time I thought I knew exactly what cam to run in anything. I realized that the smarter I got the less I knew. I have been using Schneider cams in everything I build, from warmed over stockers to all out race cars. I have a soft spot in my heart for flatheads and have learned to call Jerry at Schneider with my needs. I used to tell him what grind I wanted and he would listen to me and ask many questions. Then he would pause and say nope, you don't want that grind. I'll grind just what you need. I have been using Schneider for more years than either Jerry or I care to remember and NEVER EVER has he missed on the grind. I did a 276 for a friend's '43 roadster and he called to tell me that the cam was really lopey. I said "You wanted a real hot rod sound and fell" and he replied "I'm not complaining, this is great!" Another score for Schneider. Before you make any final decision. Call him at !-619-297-0227 and see what he says. You just might be VERY pleased.

[scooder]

Tub,
Here's my opinion.
The 3.55 gears are contrary to what it appears you desire. Chuck in an overdrive or gets worse. Don't know what gears are available for your rear ends.
What I would do. The 51 coupe, 276, Rochester 4jet or Carter WCFB. Cc the Edmonds heads, if they come out near 8-8.5:1 ish on your 276, use them. If there a bit too small for use as is, I'd blend away the ridge formed at the transfer to piston crown area to enlarge them to correct this, Ron says there thin, so not to much. Stock 8CM cam, some 4's (4.11 or 4.27 in the rear end or whatever is swappable) and fit the overdrive.
You'll have some real nice torque down low with the gears and the engine, real nice cruising speed with the overdrive.
With a beefy cam and 3.55's and overdrive, when in overdrive you'll drop into the rpm way below the torque peak. It'll be sluggish and drink gas. Yes it won't have a salty idle, but it'll be a lovely surprisingly quick and economic car.
The T with the 258, offy heads, super dual and an L100. If I kept the 3.55 gears, I'd swap in the old 3 speed trans from the coupe, and have a spare overdrive. Or again 4 something's in back and keep the overdrive.
This is my opinion, I think the resulting cars would be great cars in all respects. Think you'd be real happy.
Martin.

[GreenMonster48]

The engine in my avatar is a 258". I'm running a Schneider 254F cam which I believe is fairly similar to a MAX1 in characteristics. It's in my F-1 with 3.73 gears (which I will be stepping down to a 3.50 via 9" F100 rear). I think this set up would be great in your '51. Plenty of torque with the Edelbrock heads to lug the heavier car around.

[JSeery]

Moving from a 3:73 to a 3:50????

[Frank Miller]

Originally Posted by GreenMonster48

The engine in my avatar is a 258". I'm running a Schneider 254F cam which I believe is fairly similar to a MAX1 in characteristics. It's in my F-1 with 3.73 gears (which I will be stepping down to a 3.50 via 9" F100 rear). I think this set up would be great in your '51. Plenty of torque with the Edelbrock heads to lug the heavier car around.

I would think a later model 8 inch could easily handle the flathead and would be a big weight saving on reciprocating parts. The Mustangs with 210 hp came through with these. I may be wrong and sometimes you just use what you have or what fits with the least amount of modification.