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View Full Version : Tranny Decode Help

MYSTERYCHEVELLE
05-20-2019, 11:43 PM
Hoping someone can decipher this tranny stamp? Friend of mine has it and says he isn't sure what it is from??

Any help appreciated

Mike
madden
05-21-2019, 12:06 AM
P9RO1A

1969
OCTOBER
1ST day
M20 transmission


i believe this is what you have

thx
chris
MYSTERYCHEVELLE
05-21-2019, 01:09 AM
P9RO1A

1969
OCTOBER
1ST day
M20 transmission


i believe this is what you have

thx
chris

Thanks Chris. I guess I should have indicated I'm trying to figure out what brand car by virtue of the vin font and style. Camaro. Chevelle. Prius :)
bbbentley
05-21-2019, 01:36 AM
69 Camaro. Specifically a N (Norwood, Ohio) built car
ronzz572
05-21-2019, 01:43 AM
Partial vin starts with 1 for Chevrolet 9 for 1969 Norwood 1969 Camaro
MYSTERYCHEVELLE
05-21-2019, 02:06 AM
Thank you everyone!!
jl8z28
05-21-2019, 10:59 AM
Is the trans from a Z28
BARRY
05-21-2019, 11:33 AM
Is the trans from a Z28
there is no way to tell
olredalert
05-21-2019, 01:13 PM
Is the trans from a Z28

----Being an M20 I would think it odd that the trans might have come in a Z!......Bill S
ronzz572
05-21-2019, 05:47 PM
----Being an M20 I would think it odd that the trans might have come in a Z!......Bill S

I just sold a complete 69 z28 numbers matching DZ motor with Vin matched M20 muncie.
Mr.Nickey Nova
05-21-2019, 09:18 PM
M20 is geared better than a M21 or M22 for the 302...
bbbentley
05-21-2019, 10:02 PM
M20 is geared better than a M21 or M22 for the 302...

Agreed. Was going to mention that, but figured someone else may point that out.
jl8z28
05-21-2019, 11:31 PM
Just curious because its a late car My Z is 11A and the trans is P9R21B
Steve Shauger
05-21-2019, 11:58 PM
----Being an M20 I would think it odd that the trans might have come in a Z!......Bill S


A high percentage of Z28's came with M20 and believe above 30%. Talk about unusual, how a out an M 20 in several COPO's
olredalert
05-22-2019, 02:00 PM
A high percentage of Z28's came with M20 and believe above 30%. Talk about unusual, how a out an M 20 in several COPO's

----I agree with all of your thoughts on M20's in Z's. The ratios do work really well. Back in the day though it seemed like everyone ordered M-21's simply because they heard that M21's were the "performance" trans. I am mildly surprised at the 30%. Apparently there were that many people ordering Z's that felt M20's would be the better choice...….Bill S
firstgenaddict
05-30-2019, 08:28 PM
My Lemans Blue car was M20 4.10's the black car was set up that way as well...
If your buddy had a M21 3.73 car and you had a 4.10 M20 car you would swear he was pulling an anchor behind his car if you drove it.

M20 4.10 is the best gear ratio for a 302... it is SO much fun to drive and really very easy to drive stop light to stop light with 2.52 first.