Opinion on T5 drivability

[Henry Hopper]

I’m mulling over what to do with my 36..it drives nice as a stocker but I wouldn’t want to take it any great distance.

I’ve had several early Fords and I’ll be honest, the three speed transmissions really put me off driving them.The box is in fine fettle and works as well as it ever will but it’s just so agricultural, I want better ratios and slicker shifts ideally.

I’m asking people who have fitted a T5 to their Flathead ,what is it like now?Does the trouble and expense make it a worthwhile swap and do you find that you use the car more after a he swap.

[JSeery]

Might be a good question to post on the HAMB. Believe there are a lot of T5s being driven and there have been a lot of threads on the topic in the past. I have posted on the topic in several HAMB threads myself. Depending on the transmission/gear set you select, it is going to drive (transmission wise) similar to the vehicle it came out of. I like being able to couple a low rear axle gear ratio (I run a 4:11) with an overdrive. But that is with the close ratio T5z mustang STV gearing. If you go with the common S10 transmission gearing the low gear is so low you might want to drive it like a four speed (starting in second gear), but that is just my take on it.

[Henry Hopper]

Yes...I’m looking at the Ford version with the better ratios.Ive read that the S10 gearing is not ideal.

I thought it better to post it on here as the car is stock apart from the proposed gearbox swap.

[JSeery]

You are going to have to go to an open driveshaft or get one of the modified T5s that will mate to the enclosed banjo. If you don't want to post on the HAMB, it would still be a good idea to search the T5 info there, there is a lot of it.

[fortyfords]

Pm krylon32 on the HAMB, he sells the set-up and can probably tell you all you would like to know.

[TomT/Williamsburg]

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You can also convert your banjo rear rear o an open unit as the 5th gear will need at least a 3:54 , 3:78, or 4:11. As far as driveability the 5 speeds wake up the Flattie. My old 40 coupe had one and so does my avatar. The S10s have different gear ratios depending on whether it’s a world class unit (1988 or newer) or not (‘83-87).

[Tinker]

Here is a link to the Hamb, t5 thread of threads. About everything you want to know is there.

https://www.jalopyjournal.com/forum/...-links.169265/


https://www.jalopyjournal.com/forum/...rticle.171291/

[Henry Hopper]

Thanks Tom... I’ve got 4.11’s at present but have a set of new 3.54’s waiting to come over from America at present. Which set is preferential with a T5?

Thanks for the replies fellas.... it’s better to ask than make costly mistakes.

[TomT/Williamsburg]

You have to do the math - at 75 mph I am doing 2500 rpm. The flattie needs to run between 22-2800 rpm in 5th. There are formulas on line which when you plug in your tire size, rear gear ratio, 5th gear output and speed, you come up with an rpm. In my avatar when running 85 I am doing 2800 rpm - 32” tire, 3:54 rear gear, .86 5th gear, and 75 mph gives me rear right around 2500 rpm right where the flattie likes to be. Once you have figured this all out, you will enjoy the 5speed behind your flattie all the more.

[Henry Hopper]

That sounds like a great combo you’ve got there Tom.75mph cruising would be ideal for my requirements... at the moment it feels like it’s heading for coronary care at 60mph.

[A bones]

The great news you seek is here.

https://www.fordbarn.com/forum/showthread.php?t=206955

All best.

[Henry Hopper]

That seems like the ultimate installation where you get the best of both.Finding the parts here inEngland would be tricky I guess...no Jeep breakers that I know of... Ihave a friend who’s business is rebuilding T5’s, Ill show him the article and see if he can help.

[rotorwrench]

The closed drive set up would be the way to go on a 35 or 36. To take the T5 a step further is the fabrication of a remote shift tower in a more correct location for the early Fords. Folks are already doing this stuff. The T5 has a lot more support than other transmissions for parts due to their mass popularity. A person just has to get to know the parts to use for these conversions.

[JSeery]

Originally Posted by TomT/Williamsburg

You have to do the math - at 75 mph I am doing 2500 rpm. The flattie needs to run between 22-2800 rpm in 5th. There are formulas on line which when you plug in your tire size, rear gear ratio, 5th gear output and speed, you come up with an rpm. In my avatar when running 85 I am doing 2800 rpm - 32” tire, 3:54 rear gear, .86 5th gear, and 75 mph gives me rear right around 2500 rpm right where the flattie likes to be. Once you have figured this all out, you will enjoy the 5speed behind your flattie all the more.

Good write-up, two big factors are tire size and the over-drive ratio. There are several OD gears for the T5. My OD ratio is .63, so it works with a lower rear axle ratio.

[flatford8]

Search threads by...V8COUPEMAN....and he has a link to a conversion...https://www.fordbarn.com/forum/showt...+TUBE.....Mark

[drolston]

There is more than one way to skin the "driveability" cat.

The close ratio five speed will help a puny engine with low torque keep up. Or you can go for more torque and spend that cash to bore and stroke that flathead out to at least 276 cubes. I took the flathead in my heavier '41 to 284 cubic inches with a very mild cam, and put in 3.25 rear end gears. Cruises easy at 70; about 2700 rpm. I thought I might need to drop in a 29 tooth cluster to get low gear low enough, but no. I get going on a steep hill without having to slip the clutch very much. The car will pull away smoothly in high gear from 15 mph.

Just a thought! Cost probably about the same, and you do not have to butcher the frame and rear suspension.

[Bored&Stroked]

If you go with a T5, then look up the Ford Z-Spec version (still available brand new for about $2000 - checkout the following link below). But, you will have a very big RPM drop between the 1/1 4th and the .63/1 overdrive (which I do NOT like). What can be done to make the OD a lot better is switch out the OD gears to what was once known as the S80 gear set (was used in road racing). You can now buy the .80 overdrive gear sets for about $250. I just rebuilt one of these transmissions last Saturday and installed the .80 overdrive 5th gear - is for a road-racing Mustang that we have fun with.

Link to the Sebring Gears and Mods:

http://www.moderndriveline.com/Techn.../80gearset.htm


Also, note that there is quite a bit of work to get this whole transmission to fit in your frame (modifications required), make the necessary modifications for the new shifter location (floor pan), make extensive mods to support a torque-tube setup (special transmission case and machine work) or switch to an open drive. What I will say is that you'll surely love it once you have it!


One last thing to mention is what brakes do you have on the car? If you want to go 70 mph with mechanical brakes and actually stop the car in a reasonable manner, then you are in for some trouble. I find that properly setup mechanical brakes do pretty well up to about 55 or so mph.

The faster you push these cars with mechanical brakes, the more dangerous they become. This is why I'm switching over my 32 Cabriolet to Lincoln style hydraulic brakes - when I put the Columbia in it . . . I need to be able to stop the darn thing!

New T5:

https://www.summitracing.com/parts/f...03-z/overview/

[38bill]

Been running 15 years with my T5/59AB flathead and I love it. Wasn't a simple swap but it wasn't rocket science either. (Full disclosure: My ride is a pickup and its much easier to work on than a car). I used the S10 T5, open driveshaft conversion and a 3:54 rear gear. Yes the S10 1st gear is a little low but with my taller tires and the 3:54 its very drivable and overdrive is a joy. PS: I already had juice brakes.

[Henry Hopper]

Agree about the brakes, I’ve got a brand new set of Lincoln’s under the bed and 40 Fords for the rear all rebuilt.

Just making a list of parts required for the whole transmission and brake swap.It will all have to be done with the body on the chassis so I’ve got my work cut out.

I’ll try and post up any progress, thanks for the input, much appreciated.

[Bored&Stroked]

Originally Posted by Henry Hopper

It will all have to be done with the body on the chassis so I’ve got my work cut out.

I've done these types of jobs with the body on the frame . . . what a complete PITA. To be honest, in every case I would have saved time, money and a ton of aggravation if I'd pulled the body. Also, the results would almost always be better.

First of all, any fabrication/welding you have to do is really difficult when you can only access things and weld from below. There will be quite a bit of work in the frame center area - no way around it. Then think about the master cylinder setup, brake lines, wiring, etc . . . the list goes on and on.

So - seriously think about pulling the body and making your life easier and the work a lot better.

My 3 cents! LOL

[38bill]

I agree......The center section needs to be removed and to get at the rivets on top would be a big pita with the body on. It would be hard to bolt on the new parts as well. My pickup floor removes so I could get at both sides. The T5 was lowered down to the tranny mounts from inside the cab. You would have to install it pretty much just the opposite way. I also already had a panhard bar, you will need to add something sim if you keep the transverse rear spring. The only welding I had to do under the truck was to weld on the tabs for the new Hot Rod Works torque arm kit that stabilizes the rear wishbone.

[AKCJ]

I talked with the Modern Driveline guy at the GNRS. They seem to have the T5 stuff figured out pretty well. Including the shifter location.

[Ol' Ron]

I think the T-5 is the best thing that ever happened to the flathead. I don't like the S-10 unit because of the Low first gear, however for the early engines in stock applications, works very well. You have to drive one to understand how practical they really are. I like the Ford and lat GM case as this makes it easier and less expensive to install behind the 8ba style engines. The adapter is only $170, and all the stock clutch linkage can be used. I'm not sure,but I think this can also be used with a Hogs head, by drilling and tapping a few holes. I have on in the roadster.. Research your application and if you must run a closed driveshaft, compare it to a rear axle up grade.

[FL&WVMIKE]

LOTS of different trans ratios in the various T5 offerings. Just in Mustangs, you could get a 1st gear anywhere from 3.35 to 2.96, and Overdrive from 0.68 to .86 or something. Cannot remember the exact numbers, but there is a huge range. Your choice of rear axle would depend on the trans used. If you use an S10 trans, you'll probably want the 3.54. If you use a mustang unit with a 2.96 first gear, a 4.11 might be better. Just be sure to research transmission ratios before you buy one. I've not done this, so that's all I have to offer to this thread. Wise advice, would be to listen to those who have done this a few times. The guy that offers the kits would likely be a good source of info. Good Luck

[hook00pad]

I installed an S-10 T5 in my '48 Sedan several years ago, behind an Olds engine, using a Chevy 10 bolt rear end setup. It fit in the existing X-frame fairly well with only a little trimming. I didn't like the really low 1st gear, as it wound out at only about 20 mph or so, then you had a wide gap to 2nd gear. It was good for getting rolling tho. I loved the overdrive on the road, however, with a 3:36 rear end ratio, road speed was very good, keeping the RPM's down.

The trans wasn't strong enough for the Olds' torque tho, and shelled the 2nd gear pretty soon. At that point, I decided I needed something stronger, so I found a Muncie four-speed and went to work on installing that. I soon found out that room for the side-shift mechanical was nonexistent, so I modified the X-frame extensively. (I don't recommend this approach with the body on the car, for obvious reasons.) It worked out pretty well, but required a longer driveshaft and a little more floor modification for the Hurst shifter. I need to pull it again, tho and check it out, as it jumps out of 4th gear regularly. It doesn't shift as smoothly as the T5 and of course, doesn't have overdrive.

I may have to go back to a Tremec with stronger innards, as I really liked the overdrive. Even with the 3:36 gears and 15 inch tires it seems to need another gear, as RPM's are about 2500 at 60 mph or so.

[bill3337]

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Originally Posted by hook00pad

I installed an S-10 T5 in my '48 Sedan several years ago, behind an Olds engine, using a Chevy 10 bolt rear end setup. It fit in the existing X-frame fairly well with only a little trimming. I didn't like the really low 1st gear, as it wound out at only about 20 mph or so, then you had a wide gap to 2nd gear. It was good for getting rolling tho. I loved the overdrive on the road, however, with a 3:36 rear end ratio, road speed was very good, keeping the RPM's down.

The trans wasn't strong enough for the Olds' torque tho, and shelled the 2nd gear pretty soon. At that point, I decided I needed something stronger, so I found a Muncie four-speed and went to work on installing that. I soon found out that room for the side-shift mechanical was nonexistent, so I modified the X-frame extensively. (I don't recommend this approach with the body on the car, for obvious reasons.) It worked out pretty well, but required a longer driveshaft and a little more floor modification for the Hurst shifter. I need to pull it again, tho and check it out, as it jumps out of 4th gear regularly. It doesn't shift as smoothly as the T5 and of course, doesn't have overdrive.

I may have to go back to a Tremec with stronger innards, as I really liked the overdrive. Even with the 3:36 gears and 15 inch tires it seems to need another gear, as RPM's are about 2500 at 60 mph or so.

I used a World Class T5 out of an Iroc Camaro in my '33 coupe with a 4.11 geared Ford 9". I have a 383 Chevy stroker that put out 602 hp on the engine dyno and so far the trans has held together fine. I know their not rated for that, but so far so good and I have 60,000 miles on the trans. I push it hard as well, so I can't imagine a problem even with a hopped up flathead, if you use one of the World Class versions.

[jrvariel48]

I have a 1993 WC T-5 in my 35 coupe. I have a Ford 9" rear with a 3.25 posi. It works well with the 3.76 1st gear and .76 final drive

[Pete]

Originally Posted by Henry Hopper

I’m mulling over what to do with my 36..it drives nice as a stocker but I wouldn’t want to take it any great distance.

I’ve had several early Fords and I’ll be honest, the three speed transmissions really put me off driving them.The box is in fine fettle and works as well as it ever will but it’s just so agricultural, I want better ratios and slicker shifts ideally.

I’m asking people who have fitted a T5 to their Flathead ,what is it like now?Does the trouble and expense make it a worthwhile swap and do you find that you use the car more after a he swap.

I have a model A 2 door with a T5 and 8 inch 4.10 rear end.
I drive it almost every day in the summer. Not so much in winter as I don't like washing salt off the underside.
I have had a 150 hp flathead 4 banger, a 323 ci flathead v8, a 350 SBC and a blown Olds in the engine compartment at various times.
I have the #202 gear set with the .86 OD. This was the closest ratio common gear set there was available for these transmissions when I built it. I have the late synchros. I have a mechanical speedo. I have an additional bushing at the end of the tail shaft housing to reduce wear on the slip joint. I have a 2 inch rise short throw shifter also. The knob on the 14 inch shift stick moves 4 inches from 1st to 2nd. I run ATF in it and it will shift as fast as a Lenco.
Be careful with the fast shifts and big horsepower though. These things are only rated at 310 ft. lb.

Every one has different driving styles, requirements and places they drive.
One transmission and rear end setup does NOT fit all.
You have to determine YOUR parameters and build a transmission to suit YOU or you will not like the results.

[Tim Ayers]

Originally Posted by Bored&Stroked

I've done these types of jobs with the body on the frame . . . what a complete PITA. To be honest, in every case I would have saved time, money and a ton of aggravation if I'd pulled the body. Also, the results would almost always be better.

First of all, any fabrication/welding you have to do is really difficult when you can only access things and weld from below. There will be quite a bit of work in the frame center area - no way around it. Then think about the master cylinder setup, brake lines, wiring, etc . . . the list goes on and on.

So - seriously think about pulling the body and making your life easier and the work a lot better.

My 3 cents! LOL

So true. Good advice, Dale.