How can you tell if you have close ratio 4-spd

[bossman]

I have a 1976 L-82 4-speed 3.55 gear. How can you tell if you have a close ratio?
Thanks mark

 

[GTR1999]

Build sheet. I have a 75 L-82 4 spd and 355's. the tranny is a BW ST-10 WR. There weren't many CR trannies but then and they probably came with 370's too.
Do the rpms drop off on the 3-4 shift more then a couple of hundred RPM ? If so then it's a WR. If you have the tranny out then the input shaft has rings cut into it to spec the ratio. There are no stampings on the housing that I'm aware of to tell of the ratio. Muncies did had stampings on them.

 

[KenSny]

Good luck in finding a build sheet that's readable. Better to actually look at the tranny itself for a "W" number stamped on the case. The example is for my M21. The last digit will be a 2 for M21. There should be another number on the case that matches the last digits of your VIN. If that is there then it came from the factory with your car and engine.

WC2052
| | | | |
| | | | ˆ(close-ratio unit)
| | | ˆ(year built) 1975
| | ˆ(day built) 20th
| ˆ(month built) March
ˆBorg Warner

 

[GTR1999]

Ken, thank you I stand corrected. I'll double check the BW ST-10 for the numbers again. I only recall the VIN stamped into it.

 

[bossman]

Thanks for the help. Can you tell me where on tran's I sould be looking?
Mark

 

[JohnZ]

Good luck in finding a build sheet that's readable. Better to actually look at the tranny itself for a "W" number stamped on the case. The example is for my M21. The last digit will be a 2 for M21. There should be another number on the case that matches the last digits of your VIN. If that is there then it came from the factory with your car and engine.

WC2052
| | | | |
| | | | ˆ(close-ratio unit)
| | | ˆ(year built) 1975
| | ˆ(day built) 20th
| ˆ(month built) March
ˆBorg Warner

The last digit of the stamping on a Corvette Super T-10 isn't a ratio indicator - it tells the shift (1 or 2) when the transmission was assembled. The first gear ratio was indicated by a 2-digit paint code on the main case below the side cover; "HS" was a 2.64:1 (wide-ratio), and "HW" was a 2.43:1 (close-ratio).

 

[GTR1999]

Thanks John Z, I am corrected yet again.

I was always told there was no stampings on a BW ST-10 case to ID the ratio but nothing about painted letter codes! I have to check the pictures from the last BW ST-10 rebuild to see if they're still there.

 

[KenSny]

Thanks for the info JohnZ. I have two reference books and I guess they are both wrong. I'll have to look for that "HW", if it's still there... I know mine is an M21 as the VIN matches and the original window sticker showed the option and I doubt if the internals have been touched. The first owner saved all the original dealer supplied paperwork..... Nice guy.