hi, just starting a new project and could use some suggestions. my project is a 31 coupe with a 31 frame that is boxed and zeed. i have a 8ba flathead and i'm looking for a transmission. i found one on C.L. that is a 4 spd top loader for $275 which seems like a fair deal. my questions are, is this a good choice? i'd guess that there are a few different top loader type trans so, what should i be looking for? are there and numbers or design marks i should be in search of? are they all created equal? is there a way to evaluate the condition of it? how about bell housings? will i need a adaptor? i'm guessing that there may be some threads on this subject so i'll search here for that as well. sorry if these may sound like simple questions but, i'm new to this and thankful for the forum and any info anyone can offer. thanks!
I have no experience with flatheads but I do remember reading/hearing that a T5 out of a 4cyl S10 has ratios that work well with a flathead and the shifter position is favorable.
I'm doing a 31 A coupe with a 221 flathead. I'm using a 49 merc 3 speed with electric overdrive. It will be column shift for a bit of extra old school cool. The overdrive will make drive good on the highway. It's also a direct bolt on to the early flathead. But I'm sure you can get a fird one that bolts onto your 8ba
If you can post a picture or two, we might be able to advise you about the transmission. Otherwise it's all guesswork.
exactly^^^ What we call a top loader is a transmission with the inspection plate on the top as opposed to the side. I have noticed that what a lot of the newbies are calling a top loader is a truck 4 speed if its a late model. I have run truck transmissions but only because that is what I had to work with. If I was building a flathead powered hot rod and did not want the headache of adapting a late model ****** I would be looking for a flathead transmission. Ford ran the flathead until 54. So there is a plethora of bolt on transmissions. Transmission choice also depends on rear end choice to a point. If you are running an open driveline then a later transmission is easiest, if you are running a closed driveline than earlier transmissions are desirable. This is not to say that there is not a work around either way. Just easier if you don't have too. Any transmission that is not flathead specific is going to require an adapter.
I used an S-10 5 speed from an old pickup at U-pull-it. Used a Speedway adapter kit and it worked great! Had it in a 33 ford pickup with a flathead.
hey ya'll, thanks for the info. i need to do a bit more research but sounds like this is not the trans for me. once again the hamb has the answers! thanks
I'm slamming together a low buck flathead/39 style trans/Model A torque tube diff in a Model A frame and it's about as simple as falling off a wagon. Not sure what differential you planned on using but that will affect your transmission choice.
I actually put one in a 55 post car once. Two reasons, it was what I had is probably the only legit reason. The reason I told everyone was that it gave me a full syncro 3 speed. LOL That damned car would go faster in reverse than in double grandma. Good idea actually. One of those would work good behind a flatty. They are a little light for a more modern engine, maybe behind a stock Y block. But a good thinking out of the box alternative for a Flathead.
I did mine old school, 30 Sport coupe with an 8BA, truck transmission adapter, 41 pickup transmission, rebuilt Model A rear end with 3:54 gears. Used the stock Model A pedals with an adapter from a Model A parts dealer, this is the second coupe I've done this way, my avatar was set up about the same.
I think the T5 type is a good choice for a flathead, if you have an open drive. Another option with the closed drive shaft ( torque tube, as original) is to use the 39 top shift trans or 39-48 truck 3speed trans and the banjo rear end. the you could add a Mitchel overdrive which replaces the stock torque tube ***embly and acts like a 2 speed rear end. The Mitchel is pricey but no other adapters are necessary.
I'm not driving on the freeway but the drive ability of my coupe is fine, I'm running a 29" tall rear tire and 3:54 rear gear which works out to 2462 rpm's at 60 mph. Most people building a flathead powered car aren't figuring on running 80 on the freeway, if they are they might well use a modern V8 which has more power and is a lot cheaper than building a hopped up flathead.
I run a s-10 five speed(83- non world cl***) in my 36 five window(150 hp at flywheel says dyno) with a 3:00 nine inch 28 tall tires and 70 mph is around 2100 running around 5-8 in vacuum. Would probably do better with a 3:25–3:50 gear but had the 3:00 already so decided to run it. The car can pull the 3:00 in high gear(4th) handily but not much left when in 5th gear(overdrive) Flatheads Forever.
I put together my AV8 several years ago and opted to go with a 700r4 behind my flathead. Coupled with a 4:11 rear, the low 1st gear does a fine job launching while the O.D. handles highway speeds well. I'm very happy with it.
I'm in Kansas and we have I70, the Kansas Turnpike and I135 north out of Wichita to Salina so I don't have much expressway to worry about. A friend of mine has a Mitchel overdrive in his flathead powered 40 coupe and it works great but he still seldom runs over 65 mph. His coupe runs out great even in 3rd and overdrive but I've never felt the need for it but I also drove a banger powered 30 Model A pickup as a daily driver for almost 20 years.
yep, the only real issue I had was a bad torque convertor, had to go to a higher stall, but that was a calculated gamble. The blown flathead wanted to stumble off the line. A new 2800 stall convertor and now it's all good. Also upgraded to a fully hydraulic lockup circuit in the ****** so no more electric stuff.
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