What is the breakdown of 4 speed transmision types in 1969 Z/28's?

[68 Ragtop]

What percentage of 1969 Z/28's had the M20, M21, and M22 transmissions?

Also what percentage had an optional rear axle ratio, i.e. other than 3.73:1?

It seems that there should be a percentage approximation somewhere on CRG but I am unable to find it.

[firstgenaddict]

That is not known... it would be a guesstimate at best which would do nothing to advance factual information.
Chevrolet unlike other GM divisions and of course FORD and CHRYSLER appears to have either lost or discarded the records long ago.

[68 Ragtop]

That is not known... it would be a guesstimate at best which would do nothing to advance factual information.
Chevrolet unlike other GM divisions and of course FORD and CHRYSLER appears to have either lost or discarded the records long ago.

I realize that, and a guestimate at best will suffice. Some of CRG data information is not factual. It is based on estimates, or "guesstimates".

CRG has enough cars in the database to give approximate color usage. They should have enough Z/28's to estimate transmission and axle ratio's.

[69Z28-RS]

I could guess..       

65% M20,  35% M21, and 5% M22   .... (purely a guess based on the ones I've seen and knew about, including many back in '69). 

I suspect that if a Z28 was 'dealership/factory specified', it was M20.   If it was special ordered, then MOST buyers went with the M21, and a few with the M22 (who knew about it, planned some HD racing and wanted to spend the extra $).   The 'close ratio' 4-speed was the term you 'heard' from those ordering a new Z28 back then; it was sorta a buzz word, like 'high lift' racing cam!     I doubt all of them really knew the difference in how their car was going to drive.  By 1969, there were a lot of people ordering new Z28's who weren't not 'racing inspired'. 

[68 Ragtop]

M20 was definitely a more popular transmission across the entire line, but M21 and M22 were only available in high HP cars so looking at the  RPO number sold is difficult to decipher.

M20: 37816
M21: 26501
M22:  2117

A lot of those M21's had to make their way into Z/28's so I think your estimates for M21 is a bit low.

CRG must have enough data to estimate.

[ko-lek-tor]

don't forget....M20 included Saginaw 4 spd. in that number. On the RPO Spreadsheet PDF the # of combined 4 spds (m20,21,22) comes to 66434, but the trans usage chart near the top of page says 4spd usage total is 55813 (1969 year). Why?

[BULLITT65]

I didn't think you could get a saginaw in a 69 Z.

I could guess..       

65% M20,  35% M21, and 5% M22   .... (purely a guess based on the ones I've seen and knew about, including many back in '69). 

I suspect that if a Z28 was 'dealership/factory specified', it was M20.   If it was special ordered, then MOST buyers went with the M21, and a few with the M22 (who knew about it, planned some HD racing and wanted to spend the extra $).   The 'close ratio' 4-speed was the term you 'heard' from those ordering a new Z28 back then; it was sorta a buzz word, like 'high lift' racing cam!     I doubt all of them really knew the difference in how their car was going to drive.  By 1969, there were a lot of people ordering new Z28's who weren't not 'racing inspired'. 

I am not a mathematician  but 65% + 35% + 5% ? wouldn't that be 105% . Somethings gotta give there so how about 65, 30, and 5.

[69Z28-RS]

Nope.. Z28s are *athletes*...   Haven't you ever heard athletes on TV tell you they are giving 105% or more? 

[68 Ragtop]

On the RPO Spreadsheet PDF the # of combined 4 spds (m20,21,22) comes to 66434, but the trans usage chart near the top of page says 4spd usage total is 55813 (1969 year). Why?

Interesting observation. The total of all 1969 transmissions is 256,561 yet only 243,085 cars.

Where did the extra 13,476 transmissions go? The bulk of the discrepancy is in 4 speeds, 10,621. Maybe they went out the back door on 3rd shift!

So much for accurate RPO numbers...

http://www.camaros.org/pdf/options.pdf

[Steve Shauger]

Obviously it's only a guess but based on the cars I've owned and certified I'd say the breakdown is:

62%=M21,  35% =M20,  and 3%=M22

[BULLITT65]

maybe a poll would help..... (see the new poll)

[Hans L]

Here's my SWAG based on production numbers and assuming even distribution across solid lifter engines suggests around 8.5% of the Z's could have had an M22.

Here's the logic - In 1969 M22's could only be ordered with solid lifter engines.

So, '69 Production Count of Solid Lifter Engines:
Z28's:             20,302
L78's:               4,889
L89's:                 311
COPO 9560:          69
COPO 9561:     ~ 800

Assume 30% of the L78/89's & COPO's came with automatics or about 1820; balance of 4,248 had manuals.  NOTE:  THIS IS A SWAG....I do not have data to quantify this guess.  If its less, just fewer Z's had M22.  

Net total number of solid lifter engines that had manuals that qualified for M22:   24,503.   Again assumes 30% of the big block solid lifter cars had automatics.

Total M22 production:   2117

% of total solid lifter cars that had M22's:   (2,117 M22's)/(24,550 solid lifter engines) = 8.6%

Again, assuming M22's were evenly dispersed across solid lifter engine Camaros in 1969, would indicate a little over 8.5% of the Z's had an M22.

Lots of assumptions here and nothing absolute, but might be indicative....of course, if the bulk of the M22's went behind L78/L89's and COPO's, then the Z % with M22's could be quite a bit less.

By the way, my Z came with the M22.    Dealer car sold off of the lot per the original owner when I asked him.  No idea why the dealer opted for the M22.

Hans

[68 Ragtop]

maybe a poll would help..... (see the new poll)

Poll is a good idea. I am also interested in the rear axle ratio since the M20 and M21/M22 have different first gear ratios. I find it odd Chevy does not change the standard rear axle ratio based on the transmission first gear ratio since that can make a big difference in drivability. Please excuse, I am going to make a new poll including axle ratio's.

The reason I am looking for this information is a friend just bought an Ebay special X33 car with NOM but supposed to have original transmission and rear end. I thought the info would already be researched, but have not been able to find it. I have not seen the car yet, and am waiting for him to get the numbers.