Trans
 

No you could not get a 327 with an M21, I posted the Power Team chart, find on there any other engine than an L72 that lists the 4-Spd Close Ratio Trans???

Paul Winvoices

hello folks.
after consultation with some others, i am being told what i have is a true L72 due to the 2Q code, the date correct M21 and date correct 4:88 12 bolt, exactly as some of you noted.
i also failed to mention the car has a transistorized ignition, which also makes sense.

if anyone would know where i could source what i'm missing, like the tach, idler pulley, correct exhaust manifolds and date correct original block, i would be really appreciative.

also, id like to register this with the right group and/or find out if the car is already registered.
anyone know how to go about that?..

any help would be appreicated

It's in my research database from when I previously saw it for sale. Nice to have the extra data! Can you get a pic of the partial vin stamp on the front, side of the trans, opposite side from the date code? Also, look for a metal part number tag attached to one of the side cover bolts.

It's one of the last L72's built for 66. Janesville production ended 2nd week of June but your vin, 6J301893 is only 42 from the end of production there, which was 6J301935!

I have data on 22 66 L72 2nd sedans

wow!
that's great info and great to hear.
i will carve out some time to get under there and get those things you are asking for.
gimme a little time and i will.
thanks again!

Are you near Albany NY by chance?

im not, actually.
im downstate in the boros.
whats up?

my brother is up near Albany. Thought maybe he might run into you at a local cruise night

i have family up in Troy, but i'm not getting up that far with 4:88s...lol

So anything 1966 full size L72 gets my attention, so I was following this thread. The transmission discussion brought up things for me again and I found a document I had been putting together and thought I would post it.

Transmissions in these cars and the cowl tag always puzzled me some. L72 full size cars in 1966 were available with M20, M21 and M22. There was also the 3 on the tree option too. In regards to the M22 in full size cars, GM documentation says only 2 cars were produced at the factory. While close ratio transmission cars had a "2Q" as an indicator and wide ratio transmissions had a “2L”, it seems that not all plants used the same codes, especially BOP (Buick-Olds-Pontiac) plants.

I always wondered why Fisher body needed to know if the trans was close or wide ratio. I figured all they needed to know is if it was going to get a 4 speed or automatic. I had a conversation with Leigh Scott (who is a '66 Full size fanatic and retired GM 35+ year employee) about it and he said;

"All transmissions in 1966, except for Muncies, the speedo cable came out on the drivers side. The Muncie for '66 came out on the passenger side. In 1965, for the M20 Muncie, the speedo cable came out on the drivers side, the M21 came out on the passenger side, hence the reason (I believe) for the "Q" to denote the close ratio M21 and the need for the passenger side speedo cable clip on the floor pan. Old habits die hard, so that's why I think the "Q" lasted for 1966.”

He also mentioned that the rear axle gear ratio had an impact on if the trans would be close or wide ratio. It seemed that cars with low gear ratios got wide ratio transmissions. Paul (fsc66) posted documentation to reflect this as well.

So over the years I’ve kinda built a little list of 1966 L72 Caprices. The trans codes and gears didn’t always jive and I believe that Leighs reasoning on the codes makes sense.

Here are some known examples:

3.31 (DH code) and an M20 no trans code on tag (Doraville BOP plant built) 04D 16647 Caprice
3.73 (DM code) and an M21, 2Q on the tag (Atlanta plant built) 01B 16647 Caprice
3.73 (DM code) and an M21, 2L on tag (Norwood plant) 12C 16647 Caprice
4.10 (DN code), 2L on tag, wide ratio? non original M20 installed (Norwood plant) 01A 16647 Caprice
4.10 (EH code metallic brakes) and an M21, 2Q on tag (Los Angeles built) 12B 16647 Caprice

Adam, your car sounds like it’s on track. The K66 TI option is a nice piece. To see if you can locate some parts you’re missing I would contact Leigh Scott via his website. He’s a great guy, full of knowledge, and does insane restorations.

https://www.detroitautomotiverestoration.com/

I am curious if you can post some closer pictures of the air cleaner, the snorkels and bottom. What is the exhaust system like, is it original, where do the tailpipes exit? The radiator looks correct. Remove your washer bottle and take a look at the side of the radiator with a good light and see if there’s a number stamped on it. If it does let us know what it is. What is the stamping on your alternator (that pulley isn’t correct, alternator could be)?

I knew they were available with all 3 trannies. M20/21/22 Contrary to what the GM literature and Paul say.
I know the owner of 1 of the M22 cars. Almost every option on that car...

Leigh
 

I sent Leigh a message, curious as to what he will have to say

Paul

He has these cars on his list.

L72
 

Yes, if you had an L72 motor the only Transmission available were the: M13, M20, M21 and M22. Pretty sure what we were saying was if you had a 66 Full Size with a 2Q code (M21) on the trim tag, it has to be paired up to an L72.

Paul, I wasn't disagreeing with that fact. Just passing on some facts that I did some digging on along with some great input from Leigh.

Please note that BOP run plants like Wilmington Delaware
cars have "no" trans code on the trim tag.fortunately
My Wilmington produced L72 has not only a build sheet
but also its born with Engine and rear end.

Speedy, thanks for confirming on BOP plants doing things differently.

Paul never said that you could not get an M20 (or an M22, or an M13) with the L72 engine. He said (correctly) that you could not get an M21 (in a full size car) behind any engine except the L72.

The "literature" he posted says the exact same thing. Go back and look at it again. It shows "4-Speed Close-Ratio" and "4-Speed Wide-Range" and "Special 3-Speed Full-Synchro" as available transmissions behind the L72. (M22 was never listed in the showroom materials in 67 or earlier, hence why so few were built.)

The point is simple: 2Q means M21. M21's only came behind L72's (in a full size car in 66). Therefore, 2Q necessarily means the car came with an L72.

That does not mean (and no one ever said) that every L72 must have 2Q on its trim tag. An L72/M13 or an L72/M20 would not have 2Q. And even some M21 cars (depending on where built) were not coded 2Q.

But if 2Q IS on the tag, it was an L72.

The 2Q explanation above is correct, except that the 1965 Muncie M20 switched to the passenger side speedo cable around the beginning of the 1965 calendar year. That should not have created a problem since all passenger car M20's were Muncies in 65 (except Corvairs). So they just needed to recode 2L as requiring the passenger side speedo.

But it does not appear that that actually ever happened, which is when the confusion around the 2L and 2Q began. I have seen numerous factory M20 65 Chevelles built after 1/1/65 (including many Z16's) that have a cable clip spot welded on the driver's side floor pan, and another one screwed on on the passenger side (which would have happened on the assembly plant side, not in Fisher Body).

The confusion continued throughout the 66 and 67 model years, but it got even worse in 66 when the Saginaw M20 came out, which has a driver's side speedo cable. So now you had some 2L cars with the cable on the left, and some on the right.

For Chevelles in 66 that was not an issue, except for ElCaminos. In all body styles except the Elc, only SS's got Muncies in 66 because all small block M20's were Saginaws. So if the trim tag was a 138 series with 2L, then Fisher Body knew it was a passenger side speedo. If it was 132, 134 or 136 with 2L, then Fisher Body knew it was a driver side speedo.

But on a 66 V8 ElCamino (134 or 136 VIN'd) with 2L on the tag, Fisher Body had no way to know which speedo clip was needed unless they checked the engine RPO for the car on the broadcast paperwork, to see if it was a big block or a small block. For that reason it is common to see 66 and 67 Elc's with the Saginaw clip spot welded on the driver's side (by Fisher Body), and another clip hand-welded along its edge to the pan on the passenger side (which probably happened on the assembly plant side, and not in Fisher Body), or sometimes screwed on (which would have happened on the assembly plant side, and not in Fisher Body).

The situation got worse for Chevelles in 67. With the return of the L79 engine (which received a Muncie if a 4-speed was ordered), there was now the possibility that ANY model number (even a wagon) could be coded 2L for a Saginaw or 2L for a wide ratio Muncie. So again it is common to see a 67 2L car with both clips.

But just like for the 66 big car L72, there is at least one absolute truth around the 2Q code for 67 Chevelles - If a 67 Chevelle that is not an SS and not an ElCamino is coded 2Q, then it came with an L79 engine. (A 2Q Elc could be an L79 or a 396.)

As to the axle ratio discussion, the order forms in 66 did not have two different boxes to affirmatively choose between a wide ratio or close ratio 4-speed. So if you ordered an engine that could be paired with a Muncie M20 or M21, and just checked the 4-speed box on the form, you got whichever ratio Muncie that Chevrolet determined was best for the engine / axle combo the car was ordered with.

But you COULD override that default choice and specify whichever ratio you wanted if the salesman knew to write it in the Additional Options / Special Instructions section at the bottom of the order form, with one exception -- you could not get an M20 with a 4-series axle. 4-series axles required an M21 (or M22).

Then in 67 they changed the order form to give two different lines and check-boxes for the wide ratio and close ratio transmissions, so the salesman could more easily specify what the customer actually wanted.

And Framingham and Norwood used 2L for both M20 and M21 in 66, which adds to the confusion!

I'll have to check my list to see if it's entered. Can you PM the last 6 of the vin? I have a number of 66 Wilmington L72's in my list.

Amazing info , Jeff/Paul et al....:worship:

That's one thing that I was wondering! My Norwood car has 2L and 4.10s. 4.10s would have pushed for an M21 to be installed in it. The other car on my list had 2L with an M21 and 3.73s.

Adam, I'm sorry I kinda made the thread go sideways on ya. PLEASE post more on your car. I'd still like to see some of the details I was asking about. I'm sure others do too.

it's ok Mark.
i'm enjoying the knowledge being thrown around.
will try to get under the car this weekend and report back.

was anyone able to confirm if this car was on the list already and if there was any prior info?

also, prior to mentioning leigh scott, he was brought to my attention and i emailed him through his site.
if anyone has another way to contact him, and can pass it along, it would be greatly appreciated.

thanks.

Leigh
 

Leigh will get back to you, he’s just extremely busy with his restorations.

Paul

It was only in my list from when it was for sale in MN 2 years ago. Is that where you got it from?

yes, Minnesota.

for the tranny, here is what i got:
tailshaft - 3857584, which i think can be any used on all
case - 3885010, which i found means 65-67, so that is in line
date code - P0630, which i believe is june 30th and the fact that it doesn't have another letter in it says it is pre-67.
i don't see the tag, but ill check again
i threw in a pic of the rear code as well.
Attachment 292507

Attachment 292508

Attachment 292509

Attachment 292510

Attachment 292511

The partial vin on the trans is on the pass side towards the front on the vertical flat edge

TAR6569,
see the pic of the trans vin.
numbers matching.

Nice!

thanks for your help with finding it

And no metal part number tag on one of the side cover bolts, right?

not that i can see, but ill check again.
pass or drivers?

Side cover would only be on the drivers side, Adam.

thanks Bill