<VV> 140 hp Engines - Powerglide vs 4 speed

Bill Hubbell whubbell at cox.net
Fri Nov 18 09:41:21 EST 2005


Just catching up on a number of old VV posts, and I must admit even a 
veteran Corvair person like myself found this thread confusing, because you 
guys were not all talking about the same setups.  Just to clear the air for 
all involved, and especially those new to the hobby, I would like to 
introduce the following information.

DISCLAIMER: The following information is not all-inclusive - some exceptions 
are known to exist.

There are eleven different engine suffix codes for the 140hp engines, and 
this breaks down into roughly 8 different engine types:

(MT=Manual Transmission, PG=Automatic Transmission, CAC=Car Air 
Conditioning, AIR=Air Injection Reactor)

Type #   Engine Code(s)  Application
1            RM, RB            MT (RB has thermister for CORSA)
2            RN                    PG
3            RZ, RR             MT with CAC  (RR has thermister)
4            RY                    PG with CAC
5            RQ, RT             MT with AIR (RT has thermister)
6            RX                    PG with AIR
7            QQ                    MT with CAC and AIR
8            QR                    PG with CAC and AIR

Now to add to the confusion, there are 6 different possible Transmissions 
that were made from 1965-69, but if you count the ones from previous years, 
there are a total of 11, of which 10 have uniquely different drive 
characteristics

Type#              Application
1                      1st version 3-speed (1960 - aluminum case)
2                      2nd version 3-speed (1961-3)
3                      3rd version 3-speed (1964-5)
4                      4th version 3-speed (1966-9)
5                      Early FC 4-speed (1961-3)
6                      1st version car 4-speed (1961-3 and 1964-5 FC)
7                      2nd version car 4-speed (1964-5)
8                      3rd version car 4-speed (1966-9)
9                      Powerglide (60-3 and 64-9  64-9 designed for 164cu 
engines)
10                    140-Powerglide (65-9)

Finally, there is the Differential to consider - seven versions (4 for MT, 3 
for PG), representing four different ratios:

Ratio:                Applications
3:08:1               Special  Application - 1963 only (4-speed MT)
3.27:1               Standard Ratio for all MT cars and low HP PG
3:55:1               Standard ratio for higher HP PG cars, 64-5 FCs, Turbos, 
and cars with CAC and/or AIR
3:89:1               Standard ratio for FCs 60-63

Note that the 140-PG engine was meant to be mated to the 140-PG transmission 
and a 3:55-Powerglide rear axle to give optimum performance.  Also, if the 
car was equipped with either AIR or CAC the engines were modified to have 
lower compression ratios, and this also affected performance.

Finally, and this should be obvious, the 140 was never offered for early 
Corvairs (1960-4).

So please, if you are going to have a discussion of the differences between 
140-MT and 140-PG be sure to state which 140 engine you are using along with 
which transmission and which differential.  You certainly cannot expect that 
a 140-PG CAC engine installed onto a 1964-5 four speed with a 3:89 
differential to perform as well as a 140-MT engine mated to its proper 3rd 
version 4-speed MT and 3.27 differential!

Bill Hubbell









More information about the VirtualVairs mailing list