Best transmission for street/strip

[Gunstar1]

I have a 1977 Firebird with a Chevy 305 and a TH350 attached.

What I'm looking to do is yank both out and replace it with a PMD 400. I want the car to be streetable, yet drag race on weekends. I'm hoping to build it up to a low 13, high 12 second car, but I'm trying to decide which transmission to use.

Manual is out because I plan to run bracket racing. Manual is a big no-no for that.

I doubt a TH350 will last long under those conditions (if I'm wrong on that, please let me know)

A TH400 would take the punishment, but I've heard that they cut HP output by 45. A TH400 would also require moving/modifying the transmission crossmember.

What about the TH375? I hear that it's stronger than the TH350, but doesn't drain the HP like the TH400 does. Plus, doesn't it use the same housing and frame mounting at the TH350?

I think the TH375 was used in the full size Pontiac, Olds, and Buick cars.

Any suggestions?

[MrPbody]

You're right. TH350 won't live long behind a potent Poncho. I never had much faith in it anyway, as anything with an "anti clunk spring" is suspect (no bull, there's a part in there with that nomenclature). They tend to break the middle out of the case.
TH400 is far superior, and in general, superior to ALL other automatics, especially on a high-torque engine such as the Injun. It's not only more durable by using bigger/tougher parts, it has a unique power flow and shift process, making it much more efficient. Unfortunately, the bigger parts come with a price, and that is the 40 or so horsepower you may give up. In a heavier car (over 3,000 lbs.), it is the best trans to use with the Pontiac. It is said in a lighter car, PowerGlide can be adapted to fit, and may give a slight edge in 1/4 mile. The Pontiac won't really notice the parasitic loss of power as much as say, a small block.
Rick Holladay runs a '65 GTO ragtop, 3,700 lbs. with a 4-speed. He has won three bracket meets this year. The engine is a 434 CID Pontiac with Edelbrock heads, but a hydraulic, flat-tappet cam. It goes 12.20 all week, and even on weekends! he drives the car (93 octane) 100 miles from Virginia Beach to Richmond, races, and drives it home. While it may not be as "easy", one can definitely bracket race a manual transmission. And, if the car is to see more street time than track time, a manual gives MUCH better performance and drivability.
Be sure to get Jim Hand's book, "How to Build Max-performance Pontiac V8s". It is the current comprehensive study in Injun power.
Feel free to contact me, too. ([email protected])
You can find tons of Pontiac information and Pontiac people on the following sites:

boyleworks.com/muscle cars
classicalpontiac.com
performanceyears.com

All of these will provide you with current and accurate information regarding the Injun Engine. And no one there will say "Just put a Chevy in it..."
Welcome to the tribe!!!

[Gunstar1]

Originally Posted by MrPbody

Be sure to get Jim Hand's book, "How to Build Max-performance Pontiac V8s". It is the current comprehensive study in Injun power.
Feel free to contact me, too. ([email protected])
You can find tons of Pontiac information and Pontiac people on the following sites:

boyleworks.com/muscle cars
classicalpontiac.com
performanceyears.com

All of these will provide you with current and accurate information regarding the Injun Engine. And no one there will say "Just put a Chevy in it..."
Welcome to the tribe!!!

Thanks for the info. I have that book on order right now and should be getting it in a couple of days. I'm glad to see there is something out there dedicated to the PMD V8. My first car was a 74 Ventura with a 350 2BBL, which I later upgraded with a dual exhaust, 455 4BBL intake, and Carter Q-jet. It ran pretty good, but when I found a Rochester Q-jet from a 67 Chevy at a car swap meet, it really woke the car up.

I still have the carb, intake, and a nice pair of RA III heads to play with. Now I just need to dig up a good 400. A friend of mine has a PMD 400 and a TH400 from a 70 Pontiac that he'd be willing to sell me for $400 (irony, ain't it?). I'm probably going to go that route.

I love Pontiacs. Every car I've owned has been a Pontiac with the exception of one Oldsmobile.

Know anything about the TH375?

Thanks again for your help!