[silverbullet07]

I'm really been thinking hard about purchasing one of these M22z transmissions. I would like a lower first gear. My 2.52 and 3.36 rear is tough on my clutch on the steep hills we have. Been researching autogear and 5speed.com sites. Don't know who I should go with.

Has anyone here installed one in a Firebird?

How do you think a M22z with a first gear 2.98 and a 3.36 rear gear would perform. The output drive ratio would be 10.01 for 1st gear which would be a power horse off the line. Would it be too much?

Here is how the final output drive ratio compares. The biggest difference is 1st gear. For a performance car, the recommended 1st gear output ratio is 10.

M22Z
1st gear final drive ratio = 10.01
2nd gear final drive ratio = 6.85
3rd gear final drive ratio = 4.93
4th gear 3.36


Current M20
1st gear final drive ratio = 8.47
2nd gear final drive ratio = 6.31
3rd gear final drive ratio = 4.91
4th gear 3.36

What do you all think about this swap?

[Scarebird]

I am missing something here. I have a M22Z in my 71 - drove it last night. With 2.93's and 225-70-15's I am around 2,100 rpms at 65. The idea of this trans is a 5 speed gear spread (0.82 OD) with 4 gears. They originally meant the trans to be used with 3.08 gears (very common).

Your 3.36 with wide ratio trans is a good around town with occasional highway use. My friend's 70 Camaro has a ST10 with 3.31's so I know how it feels. I am wondering how your clutch is having issues; Dale's Camaro does fine - maybe a better McLeod clutch?

[silverbullet07]

For a street driven car, for optimal performance you want your first gear final drive ratio (trans gear x rear end ratio) to be between 9 and 10. Anything over 10 and the car will be less desirable for street application and more for strip in my opinion. Any thing less then 9 you will have to slip clutch. So a m20 with a 2.52 fist gear and a 3.36 rear the final drive ratio is 8.46. It is ok but I would rather have a little more first gear to make it more fun. I would rather be in the performance area and with a 2.98 first gear, it would put the final drive ratio 10 perfect for performance.

Moving the car with the 3.36 gears and the m20 is fine. however I live in the mountains and we have some steep hills that you have to pull out from a stop. It is a little hard on the clutch because you have to slip it some to pull out. The 2.98 first gear would help me on that as well.

Your 2.98 first and 2.93 is 8.73 which is better then I have now and closer to that 9. The M20 with 3.55 rear gear would probable have been perfect for me but I would have higher 4 th gear rpms then. With the m22z the 4th gear rpms stay the same that I have now.

Your friends ST10 may have a 3.42 first gear with a 3.31 rear. His final drive ratio in 1st is 11.32 wow. now that is very steep non street 1st gear. he barley moves before he is shifting from 1st,
If he as the 2.64 first gear, then his 1st final output ratio is 8.73 which should feel like yours. Also you may have more lower end torque to help you as well.

By the way, I contacted Paul Cangialosi at 5speeds.com and he thought the m22z would work great for my application.

[keith k]

The M22Z gearset sounds like a nice spread for a big Pontiac engine.
Is it possible to install these gears in an original M20/M21 case? (I would like to keep my matching-number trans case...).

[TedRamAirII]

Originally Posted by keith k

The M22Z gearset sounds like a nice spread for a big Pontiac engine.
Is it possible to install these gears in an original M20/M21 case? (I would like to keep my matching-number trans case...).

Yes. Just buy the gearset. It uses a 1" counter shaft, and you can get it with 10 spline input shaft, so it should go right in your original case. You may have to replace the front bearing retainer as I think the new shaft uses a oil seal, and add a vent. But call Paul to confirm. http://www.5speeds.com/cart/index.ph...&product_id=60

[Scarebird]

Note: I bought mine at 5speeds.com form Paul. Only issue was fitment of the output yoke - my stock one did not fit. Buy one of his fitted.

[silverbullet07]

Originally Posted by Scarebird

Note: I bought mine at 5speeds.com form Paul. Only issue was fitment of the output yoke - my stock one did not fit. Buy one of his fitted.

Did you have a 10-27 input output shaft. I asked if anything would need to be changed and he said no. Have any idea why it was different on yours?

My shifter is real close to the tunnel side. The top mounting bolt is right against the tunnel which does not allow much wiggle room. How is your shifter mounted? I have the adapter plate on hurst competition shifter. Not using athe c-clamp mounting plate.

Trying to think all these things through.

[Scarebird]

Originally Posted by silverbullet07

Did you have a 10-27 input output shaft. I asked if anything would need to be changed and he said no. Have any idea why it was different on yours?

My shifter is real close to the tunnel side. The top mounting bolt is right against the tunnel which does not allow much wiggle room. How is your shifter mounted? I have the adapter plate on hurst competition shifter. Not using athe c-clamp mounting plate.

Trying to think all these things through.

no, mine has the M40 output shaft and the 26 input shaft. Shifter I found was a Pete Serio rebuild - very nice, uses the stock 71 GM mount plate. I bought the rods from our sponsor - every one needed cutting and rewelding to clear correctly.

The nice thing about these trans is that they are completely backwards compatible - the GM stuff bolted up. Only difference is that the SuperCase is a bit thicker at the mount ears, requiring special bolts and the speedo is passenger side ala Chevy.

Another post after install:
http://forums.maxperformanceinc.com/...highlight=M22z

[silverbullet07]

My 68 Muncie has the speedo on the passenger side. Must have been a 68 thing or earlier. Thanks for the link on your after install.

[TedRamAirII]

Far as I know...........all new housings 27 or 32 spline are all passenger side speedometer.
http://www.5speeds.com/cart/index.ph...5_17_69&page=2

[unruhjonny]

Originally Posted by silverbullet07

For a street driven car, for optimal performance you want your first gear final drive ratio (trans gear x rear end ratio) to be between 9 and 10. Anything over 10 and the car will be less desirable for street application and more for strip in my opinion. Any thing less then 9 you will have to slip clutch.

This is good advice, but should be taken with a grain of salt.

I drove my Firebird for years with 3.55:1 & an M22;
2.2 x 3.55 = 7.81

I did not have to slip the clutch...
It drove fine.

I'd wager it has more to do with the torque curve than pure calculated nubers, otherwise Pontiac would never have made the base '73 Trans Am drive train as the M21 with 3.42:1;
2.2 x 3.42 = 7.524

I personally would stay away from too deep of a first gear combined number - it makes first gear kinda useless - but then again, that seems to be the norm for most cars;

2015 Camaro:
SS w/6spd = 3.01 (1st gear) x 3.45 (FDR) = 10.38
SS-1LE w/6spd = 2.66 (1st gear) x 3.91 (FDR) = 10.4006

2015 Challenger
R/T = 2.97 (1st gear) x 3.90 (FDR) = 11.583

2015 Mustang
Performance Pack 3.657 x 3.73 (FDR) = 13.640

...and even my Cobalt (which makes over #300 pretty quick);
3.38 (1st gear) x 3.82 (FDR) = 12.9116

[silverbullet07]

Yes that is good advice. when you had your Firebird with a 3.55:1 & an M22; 2.2 x 3.55 = 7.81 Did you live in the mountains and stop on very steep hills? I'm not sure what the terrain is like in Calgary, AB, Canada. Here in the blueridge mountains and were I live, there are some very steep hills and a stop sign at the top. the m20 2.52 and 3.36 is ok for that but 3.55 would help. I would hate for the rear end to have lower numerical number like when I had 2.73 gears in.I burned the clutch all the time trying to pull out. Put two people in the back seat and the clutch would be smoking. Maybe may clutch was not adjusted correct but with a ratio of 6.87 it seemed bad.

[unruhjonny]

Hense "taken with a grain of salt";
I will not argue with anyone that the 2.20 1st gear with a 3.55: was less than ideal - but it was offered that way from the factory more than once - I just chose the lowest hp & least ideal gear combination (1973 L75 & M21) as the worst case in which Pontiac offered it.

This was also the standard gear combination that the 1971 & 1972 Trans Am's came with.

Like I said, I suspect that torque is the key factor in making this less than ideal combined first gear ratio liveable - it would probably be painful for a low compression 400, and even worse in a 350.