Question: L82 4-speed RPM vs MPH

[Toad75]

I purchased my 1975 L82 last fall, so I am into my first full season with the car...what a ride!!

I was wondering, though, if something is a little off...maybe the transmissions was re-geared at some point for greater low end performance.

Does anyone know where to find an RPM vs MPH graph for each gear.

The spec sheet states 3.55 rear end, with a 4-speed manual - wide ratio tranny.

I am new at this, any help would be appreciated.

 

[Copdogcorvettes]

WELCOME TO CAC. Check on the Keisler Site, they have a speed calulator section to compare the stock trans to their 5 speed.

Gary

SAVE the WAVE

 

[KANE]

I purchased my 1975 L82 last fall, so I am into my first full season with the car...what a ride!!

I was wondering, though, if something is a little off...maybe the transmissions was re-geared at some point for greater low end performance.

Does anyone know where to find an RPM vs MPH graph for each gear.

The spec sheet states 3.55 rear end, with a 4-speed manual - wide ratio tranny.

I am new at this, any help would be appreciated.

You should be pushing approx 3500 @ 70 mph in 4th. As for the other gears, they will be a derivative based upon their ratio to one (which is 3.55 for your rear end).

Here is a site that calculates what you are looking for-

http://www.smokemup.com/auto_math/mph_range.php

 

[73shark]

My '73 L-82 4-spd (wide ratio) w/ 3.55 rear and 255/60-15 tires goes 22 mph/1,000 rpm.

BTW

 

[Toad75]

Nice!!! We have similar tastes...

 

[GTR1999]

I gave my 75 L82 M-20 355 Gymkana coupe to my son a few years ago. I liked the stock setup once we installed 2.5 true duals. He didn't and now the car is pushing 375 hp +/-20 hp, just rebuild the ST-10 and we swapped the 355 for 373, 336, and now 411's.
I still like the 355's with 375 hp it was nice.

 

[Jimmy C]

I don't have a 4 speed, but a TH350 automatic. For a small block chevy, or a BB, a steady 3000 rpm isn't friendly. At 70 mph 2200 to 2500 rpm is comfortable. At 70 mph, my tach reads 2800 which is a drag on a long trip. Around town, the 370s or the previously mentioned 4:11s are fine, but on the highway, they're not happening. Maybe you can find someone to reply to your topic who's found a friendly highway gear ratio f/ your 4 speed tranny. Good Luck.