Is it possible to have a Muncie M-22, factory installed in a 1972 350 LT-1?

 

Yes.

 

Twenty of them to be exact.

 

Kinda really rare if you know what I mean. Gonna need a tank sticker to back it up.

 

I believe that the M-22 was only available in the 72 LT-1, as part of the ZR-1 package. The M-22 could not be ordered with a "regular" LT-1, or either of the other 72 engines.

 

Only with the ZR-1 package. Source:

http://www.gmheritagecenter.com/gm-h...t-Corvette.pdf

 

Quote : Only with the ZR-1 package.

So then where did the other 20 go ?

I would have a close inspection done of the ser # stamp on the block and compare the characters irregularities to the stamp on the tranny . It is probably easyer to fake the paper work than the stamp .
The same guy that stamped the block used the same gang stamp to stamp the tranny .

Same deal for 71, about 10 more M-22s than ZR-1s . Maybee Johnny Cash took them home in his lunch pail ( 1 piece at a time )

Bill

 

There was no "other 20", there were only 20.

The only way to get an M-22 in 1972, was to order the ZR-1 package. It was not available any other way.

The 20 72 M-22's, went into the 20 72 ZR-1's.

There were 130 1971 Corvettes built with the M-22. Besides coming with the ZR-1 (of which 8 were built), it also came with the ZR-2 and for an additional $100, it could be ordered with any 71 Corvette equipped with the 454 LS-6.

 

Where did you get your figures?

 

Various 1971 and 1972 Chevrolet sales brochures and dealer literature, along with NCRS Specification Guides.

The 1972 Corvette sales brochure notes that the the ZR-1 package includes a "Special 4 Speed Transmission" (Chevrolet's sales term for the M-22), while the rest of the brochure, only refers to the standard wide and close ratio transmissions. I've never seen any 72 Chevrolet ordering information, listing the M-22 as a separate RPO. It only seems to turn up in reference to the ZR-1 package.

Under the production figures for 1972, the NCRS lists the M-22 as follows: M22 Heavy-Duty Four-Speed (w/ZR1)....14 Coupe...6 Convertible...20 Total.

J56 Heavy-Duty Brakes and F41 Special Suspension are also listed the same way and with the same production numbers.

For 1971, the M-22 production numbers can be found in a number of places, including the NCRS Specification Guides and The Black Book. 130 is given as the number of M-22s ordered in 1971.

The 1971 Corvette sales brochure makes no mention of the ZR1 or ZR2 packages (not surprisingly, neither does the 1970 brochure). The only mention of the M-22 is in the engine section, where it states "A Special 4-Speed close ratio box is available with the 425-hp V8.", and in the engine chart, where 3 transmissions are listed as being available with the LS6 454. Those transmissions are the Turbo-Hydra-matic, the 4-Speed (2.20:1 low) and the Special 4-Speed (2.20:1 low).

The 130 M-22's probably ended up behind 130 of the 188 LS-6's built. There were probably 8 more M-22's in the 8 1971 ZR-1's, and maybe 12 more M-22's in the 12 ZR-2's. I'm not really sure if the ZR-2 package required the M-22, or if it could be had with a Turbo-Hydro.

 

OK... Your turn. Where did you get your figures?

 

Thanks for the info , do you know of any LT1s with the M22?

Thanks Bill

 

Yes. There were 53 total LT-1's built with M22 transmissions, all of these were ordered with the ZR1 option (M22 was a mandated part of this option).

In 1971 130 M22 transmissions were ordered from GM records on the Corvette model. 8 of these went into LT-1's ordered with the ZR1 option package. Another 12 wento into LS6's ordered with the ZR2 option package. The balance of 110 were ordered with the LS6 option for the Corvette.

 

Sorry, I meant were there any plain LT1s ( not Zr1, ZR2 or LS6 ) with the M22 ?

Bill

 

No.

 

I have seen a 71 LT1 nwith an M22 .

 

I've seen several as well, unfortunately everyone of these had been changed out, some had fraudalent documentation made to support their claim of a factory installed M22 transmission without the ZR1 ordered option. The 1971 Corvette Order Forms don't give the customer the choice of this transmission when the LT-1 engine option is ordered without incorporating the ZR1 off road package.

 

I believe it to be real . Just because there was not a box to check at the dealership does not rule it out. The engine pad stamp and the tranny stamp were identical on this car .
Lots of things can and did happen .

 

Some of the original gang style holders and stamps are still being used by individuals in restoration shops today. As of yet there hasn't been an original non ZR1 '71 LT-1 ordered Corvette model that has undisputable factory paperwork to back up the M22 option.

 

Not trying to start anything here , but how can anyone say that . Just because you don't believe it does not make it so .
My opinion is just another opinion .
Regards