Beach Bum

Fellow worker has a 75, L82, 4 speed manual and apparently a rare convertible. We're trying to figure out the gears in the thing.

Does anybody know the tranny ratio's of the 4 speed manual and also the available or typical rearend ratio given.

Thanks for any help.

Cheers,
Beach Bum

Tominator

Someone will probably chim in with your answer, but if you go http://www.smokemup.com you might be able to fing your answer.

It has a section for determining rear gear, tell it your trans. and it post the gears, you'll also need to know your tire size.

7Bob3

Todd, The only thing for certain is it is a fairly rare car. The L-82 had the m-21 standard, 2.43, 1.61, 1.23, 1. It could be optioned with the m-20 2.64, 1.75, 1.33, 1. Stock gears were 3.08 but that is a crap shoot too. Could be optioned anywhere up to 3.73.

IETEK

"rear gear ratio" If you put the car in 4th gear (1:1 ratio) and go 75mph the tach will read with in a 100 rpms or so of the rear end ratio e.g. my car has 3:70 rear end ratio at 75mph my tach reads 3700 rpm this is the same for any transmission you run in a 1:1 ratio.


IETEK :D

1971Ultra

According to:
Cars & Parts Magazine, Catalog of Corvette ID Numbers, 1953 - 1993, here is how you identify your rear axle for a 1975:

THE REAR AXLE NUMBER identifies the gear ratio, the build month and day and the plant where it was assembled. The code is located on the bottom of the differential carrier housing by the cover.

EXAMPLE: AXW2131
AX = 3.36 ratio w/positraction
W = Warren Plant
213 = 213th day of the year
1 - 1st shift

Here are other ratio codes:

AX or LR - Postitraction 3.36
AC- Positraction 4.11
AB - Positraction 3.70
AA - Positraction 3.55
AW - Positraction 3.08
AY - Positraction 2.73

Other plant codes:

G- Chevrolet Gear and Axle
C - Buffalo
K - GM of Canada

Sorry I do not have anything on the tranny ratios for a 75, however I can tell that if code on the tranny ends in an A it is a M20. If the tranny code ends in a B it was optioned with the M21.

Hope this helps.

Kipp

Paul Borowski

A '75 L-82 4spd(M-20 or M-21)supposedly came with either a 3.55:1 standard OR with a 3.70:1 as a "performance option".
Yes, a '75 L-82 convertible is one of your most rarest '70's Corvettes ever made. It is one of only 366 convertibles made with an L-82. I have a letter from GM that states such. Only 2372 L-82s were made in '75, 2006 being coupes & 366 roadsters. I have 60 '75 L-82s in my Survey of them. If your friend is interested in being in my survey, he can e-mail me or instant message me ;)

Beach Bum

Interesting.... thanks for the information.

As a note, his 75 is very clean, has fresh paint.... I didn't know it was so rare.

He's not on the forum, email me the survey and I will forward to him and re-send back to you.

Thanks again :)

cheers,
Beach

Cajun99

I can only wish mine had the L82 with the four speed :lol:

Those are the only two options my car doesn't have :smash:


[Modified by Cajun75, 5:28 AM 2/18/2003]

FinnShark

1971Ultra: Very cool info!!! :cool: I'm going to crawl under my car next weekend or next week so this info came just in time! Thanks! :hurray:

Phlebotomatic

I just bought a 75 hardtop convertible, L82, 4spd, gymkhana fully loaded... Is this really that rare of a vehicle? I was planning on an engine swap in a few years to get past the shitshow 205hp. So should I keep it #s?

4-vettes

O.K. First and foremost. you should NEVER tag onto an old thread forcing everyone to read through the entire thread to get to your new question.
Please start a new thread.
Second. your L82 is a great base. put some good heads on it and a slightly better cam and proper exhaust. 400 H.P. is easy.

vettebuyer6369

You are posting to a thread thats been dead for 18 years.

Please start a new thread.