Expert: Dan Liddy - 4/14/2007

Question
Hello, I don't know if you can help me out but here's my question: I race a 78 Cadillac at the dirt track (1/4 mile) and was wondering what transmision would work best. It has a 472 out of a '74 with the T400 transmission. I was told that running the 400 transmission might be robbing some horsepower from the car and that I might do better with the T350. The car is competative as it is but there are still some chevy 305's that I can't catch. This is a very stock racing class, so I am limited as far as beefing up the motor is concerned. But I can change transmissions. The rear end gears are 228's, most run 241's or 256's, but if the 400 transmission is draining horsepower mayby the 350 will make up for it...what do you think? Thanks very much, hope you can help! ...Tom

Answer
Hi Tom:

Your choice of transmissions would depend mostly upon how much you are willing to invest in preperation and modification of the trans.  

My first inclination is to suggest you stick with the T-400 - -  a workhorse that will last and last, and take a LOT of abuse.  The T-350 is more popular with tranny shops cuz they work on a lot more of them , they're just not as tough. And hauling that huge car and huge motor is going to take a big gearbox.   Now , many of the high horsepower late model boys use a highly modified Power Glide 2 speed out of an old Chevy, but they are NOT stock.  Check with Summit racing in Akron Ohio for more details .

I can't advise you which gear to use, but you should be seeing about 5000 to 5500 on the tach just as you shut down for the next corner.  Gear for that result and you'll be close.

Good luck with it- -  quite a project you have going there, win one for me !!

Dan Liddy
Sarasota, Florida