[64woodwheel]

I am thinking a M22Z might be the way to go for a highway cruiser. With a 2.56:1 rear end and a 26" tire that would be around 2050 RPM at 60 in 4th gear.

Also 2.98 x 2.56 = 7.62 Very close to a 2.56 x 3.08 = 7.88 (standard muncie w/ 3.08 rear)


Basic info:

64 Tempest w/ 78X 389 4bbl. all stock. Stock Tempest 2.56:1 rear end.

M22Z
1st 2.98 2nd 2.04 3rd 1.47 4th 1.000

M20/21 (1964)
1st 2.56 2nd 1.91 3rd 1.48 4th 1.000

Am I on the right track here? Anything to watch out for?

[Tiberius]

I have an M22 in my TA... (That noise is incredible from the M22)

My rear gear is 3.42 and 1st gear on my M22 is 2.20

3.42 X 2.20 = 7.52 close to your 7.62

I have no problem in first gear and I prefer this set up as first gear is nice and long, and you can pull it hard as you come off the line and can wring it out longer.

My previous ST-10 was too short for first gear.. Didn't like it.. You can get away with doing what your doing as Pontiac engines produce awesome torque and you'll be fine.

[kookykrispy]

The trick here is where do you find a posi for a 2.56 gears... ?? I guess it would be ok if you have a factory posi or if you don't mind a peg-leg rear end.

[64woodwheel]

Originally Posted by kookykrispy

The trick here is where do you find a posi for a 2.56 gears... ?? I guess it would be ok if you have a factory posi or if you don't mind a peg-leg rear end.

Actually found one here in parts for sale. That was one of the key finds for making this combo practical.

[Rugratman]

M22, is really loud in a cruiser.
Also the gap between 1st and Second gear is pretty big. Not exactly a smooth shift.

I am running a M20, and with a 3.42 gear, at 60 mph, I am around 2700

Tire choice can help allot too.
Your numbers are ok, just be aware of the noise and the gap/jerk from 1 to 2.....for a cruiser.

[64woodwheel]

From what I have heard about the M22Z gear set, the m22 whine is not there in 4th. I'll have to ask one of the builders about that. Yes the 1-2 drop is pretty big, I guess that is the sacrifice for what I am ultimately after. I know the modern 5 speed overdrives are killer too. ( I want to use the stock 64 hurst shifter ) So the T56's TKO's etc. won't work for me.

[Pontirag]

put a little sawdust in it. that always got rid of the whine in tranny's and rear ends

[Cobrabill]

Cruising rpm needs to be ABOVE the point where all your timing is in.

[elefantrider]

Sounds like a good idea for street and even some strip.
How much will it cost?

I run a M20 and I am sure my car would be faster if I had a lower first gear in the 2.90-3.00 range.

And I would never put a 5 speed in my car. Would change the original feel of the car, IMO.

[tom s]

If your not going to race it with big tires find a 3.42 first gear ST-10.I have one in my 62 GP with a 3.08 in the back.WAY better than my 2.56 muncie in my 63 cat with the same rear gears.The nice thing is they usually go cheap.Just make sure the one you look for has the std shifter mount.I had one in a 63 GP with a 421 HO and never hurt it.Tom

[elefantrider]

Tom, didn't they use that trans in trucks?

[1971WARBIRD]

i found 2 3.42 gear ST-10's in 81 Trans Am's that came with 305 chevy's. one was alum case and the other is steel, always wondered about that. bought the cars just to part as they were really rusted.

[tom s]

have no clue if put in a truck.I have a fresh iron case unit I might put in my 63 421 Cat.Just hate how much I need to slip the clutch with the 3.08s and the 2.56 first muncie.Tom

[dadsformula]

Tiberious mentioned M22/3.42 combo and that is the same as my formula although
mine is an M21 it has the same ratios without the noise. The Key to this setup
that no one really mentions is the Flywheel. The 455 in 73 (not sure of other years
or the M22 combinations) used a 40 pound Flywheel as apposed to 30 pound used in
nearly all other combos. This has nothing to do with final ratio, but this does add
a lot of inersia. I can just walk my Car from a stop, and this really limits the wear
on the clutch as much less slippage occurs. This combo also came stock with
an 11 inch clutch. Point of all of this is that there are other factors for street
driving that can enhance or reduce the effectiveness of any combo. The drop
into second for example would be a real pain with a 350, but with the 455 torque
is's not really noticed at least by me. Racing is a whole new Game. Lightweight
flywheels and high rations for high reving is completely different animal. I am a
big believer in those old Pontiac engineers. For a Street Car, 64 or any other
year, consider a factory set up. They work, but i will admit i had a very difficult
time locationg a factory 40 pound flywheel for an 11 inch Clutch.