Muncie on a 400 pontiac?

I have a pontiac 400 motor built and ready to go and want to put a manual transmission behind it. I've been told that a muncie 4 speed will bolt right up and match, but I just wanted to cover my bases. I would appreciate the help from those who know more than me, Thanks

Muncie M21 W Hurst shifter

Thanks Morley, that was the plan but I wanted to make sure all my ducks were in a row. Another question, is a GM flywheel a GM flywheel or is there a difference between chevy and pontiac?

The Pontiac flywheels are Pontiac, Chevy won't do. Check here http://www.angelfire.com/fl4/pontiacdude428/pontiaccrankpn.html

Also, the M21/ Hurst combo was the one most commonly used by Pontiac.

M21 or would I do better with a T-5 or something along those lines. I have 3.23 posi rear-end and a modified pontiac 400 power-plant. I would like to have the overdrive for interstate travel and gas milage and if I'm not mistaken the gearing on the M21 was really close wasn't it? Thanks again.

M21 or would I do better with a T-5 or something along those lines. I have 3.23 posi rear-end and a modified pontiac 400 power-plant. I would like to have the overdrive for interstate travel and gas milage and if I'm not mistaken the gearing on the M21 was really close wasn't it? Thanks again.
I seriously doubt a T5 would survive behind a built Poncho engine. The RA IV engine was a nasty one and it would shread a T5. Unless you get a specially built over drive trans, it isn't going to be up to the task.
Yes, the M21 was a close ratio gearbox.

Agreed, the little 5-speed won't last long. Pontiac V8s make MUCH more low-end power than most and will eat up light duty transmissions.

Hayes and McCleod both offer an SFI-approved flywheel. You will need the correct bellhousing, too, as Chevy stuff won't fit. Lakewood makes the "blow-proof" bellhousing of choice. Finding a stock aluminum unit isn't impossible, but getting more difficult every day. Same is true of a stock flywheel.

M-20 was used in GTO and Firebird with "wide ratio". M-21 was the "close ratio", as stated. M-22 was the heavy-duty unit and available in both gearsets. M-22 is easily identified by the larger slip yoke (same as TH400). M-37 "Rock Crusher" was never offered in Pontiacs, but would "fit" if you could find all the pieces. For cars with strong low-end and taller gears, M-20 or "wide ratio" M-22 would be the more desirable. For a racer or lower-geared car, the close ratio trans would be prefered.

Borg Warner ST-10s were in the '73 and later T/As and A-bodies. Tough stuff.

Hurst shifters were all that was available until '73, when the Borg Warner shifters appeared in A-bodies. Firebirds and GTO still got Hurst.

For future reference, very nearly NOTHING that fits a Chevy V8 fits the Pontiac. I would get Jim Hand's "How to Build Max-performance Pontiac V8s" for insight into the old Injun. A current study (Summer of '04), it has lots of good information for Pontiac guys.

Jim

Thanks, I really appreciate it.

What do you think about putting in an ls1 motor in my 1967 firebird. It still has the original 326 with a 2 speed auto, so something has to be done if I want more go power! I see complete engine/tranny setups out of 98 to 04 wrecks going for about 3000 or so. Im not sure what kinda power you can get out of a 400, but my guess is that I would be spending a few K rebuilding one.
Thanks

Power from a 400? 600HP is pretty easily obtained. You could build a 400 for less than the LS engine and items needed for the swap.
I would hold on to the 326 & powerglide as the car could be worth big bucks if restored to factory if you want to revert it later to sell.

Power from a 400? 600HP is pretty easily obtained. You could build a 400 for less than the LS engine and items needed for the swap.
I would hold on to the 326 & powerglide as the car could be worth big bucks if restored to factory if you want to revert it later to sell.

The 326 is rebuilt and runs great, New bearings, rings, hardened valve seats so I can burn unleaded, and a new two barrel carb. The powerglide is good to go as well. From most everything Ive read so far, the 326 just isnt a suitable mortor to build any kind of real power plant. Do you agree?

rebuilding my 400 wasn't horribly expensive. I didn't go very radical at all and I'm expecting 450 hp and 500 ft/lbs. I just helped a friend do a conversion to an LS1 in his '90 silverado and it is impresive, but even then there were quite a few kinks along the way. I can say this, there are alot of things that you don't realize you need until you are already knee deep into the project. That goes for just about any projects I guess, but at least the 400 was a factory option.

FWIW,

The 2-speed automatic is not a PowerGlide. PowerGlide was pretty much a Chevy exclusive, though I've been told there WERE a few "bi-sexual" cases made (go both ways...). The trans in the Pontiac is a "Super Turbine 300", and shares nothing but the number of forward gears with PG. PG is much tougher and can be a good trans for drag racing in a light car. ST-300 is durable, but does not respond well to performance modifications.

Much less effort and more usable power from installing a Pontiac 400 or larger over LS-1. TH400 is the transmission of choice behind a pumped up Pontiac.

Jim