What's Behind Your Flattie?

[Black Fifty]

Hello All.

I purchased a fairly stock 1950 Ford Custom Deluxe with 239 and 3 speed with overdrive and 4.10 gear in September of 2018. In the future I plan to bore and stroke the engine to get a bit more grunt at the occasional stoplight. I have zero experience with these cars, so I have no idea what the trans will hold up to in terms of power. Previous to this car, all my toys were from the 60s and I knew what to use.

What do you all use behind your warmed-up Flatheads? Should I be cautious with the trans? Are there internal upgrades that add strength? The car is so original that I don't want to cut a hole in the floor for something like a T-5 (well maybe). And I don't want to go to an automatic.

I welcome any suggestions/comments/opinions from you folks. You guys are THE experts and I learn something about these cars from all of you every day!

Thank you.
Mike

[Seth Swoboda]

You won't have any problem with the stock 3 speed transmission behind a warmed up street flathead. Your money will be better spent on a 3.54 gear ratio in the rear end and a 29/15 tooth transmission gear combination.

From past experience building a warmed up 8BA engine, you'll see some improvement in power but the net gain is negligible to the rest of the drive train. The "cool" factor is greater than the "throw you back in the seat" factor. For me it wasn't worth the extra expense, opinions vary.

[tubman]

I agree with Seth about the current transmission being up to the job, even with a "warmer-over" engine. I think Seth may also be confusing early vs "shoebox" transmissions. While the combo he mentions works well for the earlier cars, the OD (which the O/P has) makes all of that moot. The later car with a working OD and 4.11's will be superior in every way to an early car, even with the mentioned mods.

That being said, I wonder if anyone has ever replaced a stock shoebox transmission with a T85/R11 combination. From what I understand, it should be almost a "bolt-in". Ford sold FE's with this combination behind them in the early sixties so they should be plenty strong. The only problem is availability. I have been looking for one locally for a while with no luck.

It is possible to hurt a stock transmission with a stock engine (even one that doesn't run the best) if you try hard enough. I know I got good at replacing them when i was about 19.

[40cpe]

I had a '50 during my late teens and early twenties. Believe me, if you "chirp" the tires hitting second gear a few times, you will be replacing the transmission. Back then, they were $25 in the junk yard.

[WABOOM]

Stock Merc-o-matic and stock Dana 44 with 3:31's

[Seth Swoboda]

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Originally Posted by tubman

I agree with Seth about the current transmission being up to the job, even with a "warmer-over" engine. I think Seth may also be confusing early vs "shoebox" transmissions. While the combo he mentions works well for the earlier cars, the OD (which the O/P has) makes all of that moot. The later car with a working OD and 4.11's will be superior in every way to an early car, even with the mentioned mods.

That being said, I wonder if anyone has ever replaced a stock shoebox transmission with a T85/R11 combination. From what I understand, it should be almost a "bolt-in". Ford sold FE's with this combination behind them in the early sixties so they should be plenty strong. The only problem is availability. I have been looking for one locally for a while with no luck.

It is possible to hurt a stock transmission with a stock engine (even one that doesn't run the best) if you try hard enough. I know I got good at replacing them when i was about 19.

Yes, I forget that the shoebox Ford's had an overdrive. Maybe I ought to own one so as to get familiar with them? I still think unless you are trying to tear something up, he'll be fine.

[amodel25]

I always heard that the weak link is the driveshaft pinion yoke on the stock rear end. I finally proved it a few years back (with a hopped up 226 six cylinder no less). I was 500 or so miles from home and just lucked into a replacement. I carry a spare in the trunk now.

[Charlie ny]

The T-85 is a monster and used behind big block everythings.....blown early T Birds,
'59 Olds and Buicks, 427 Galaxies, Stude Hawks with the factory 352 Packard ya da
ya da. I happen to have a fresh T-85 with OD sitting in pergatory in my shop. I'll
say you'll break a flathead before you'll break this trans.
Charlie ny

[mfirth]

I have a 52 Ford Victoria with a mild 8BA and the original Borg-warner o/d.
Love it. Just don't do clutch dumping starts....1st gear aint happy with that.

[Ol' Ron]

The early ford flathead trans with OD is not a very good trans, even with the stock engine. It works great with NORMAL driving. However the T-85 w/OD is the way to go.Many of these trans had the dual bolt pattern and would bolt right up to the flathead bellhousing.

[KGS]

Originally Posted by amodel25

I always heard that the weak link is the driveshaft pinion yoke on the stock rear end...

That's been my experience. In the late fifties, when I was young and foolish, I had a 1951 Ford CV with 1956 Caddie power. Stock '51 transmission w/ O/D and a 4.10 rear. If I ran it out of O/D I could pretty much beat any local in the quarter mile. Put it in O/D and take a run "down the shore" and average about 22 MPG. All I ever broke was the driveshaft yoke and I broke a few of them. The parts guy at Molin Ford always knew what I wanted when I came through the door. Always carried a spare. Great car, never shoulda sold it.

[tubman]

"Charlie ny"- Does the transmission you have have the early ('49-'64) bolt pattern? Do you know if the mount and shift linkage work (with minor modification)? I know you're not local, but.......

[Charlie ny]

I built the trans to go into a '57 Ford 2dr. Everything thing lined up for that applica-
tion...drive shaft , mount, linkage.
Charlie ny

[chuck stevens]

I have a c4 auto behind my 8ba in a 40, love it. The diff is 60-70's 8", 3:00. probably not the quickest thing but dependable and runs with traffic ok.

[Ol' Ron]

The trans gears are about the same as those in the early transmissions, and the OD is a 3 planetary gear set. The T-85 is a different trans with much beefier gears and a 4 gear planetary. hard to believe the early box stood up to the caddy at the drags.

[Black Fifty]

Thanks for the responses guys. You've given me a lot to think about. At least I know a little more about it now than I did.
Mike