cabotgsxr

iTrader: (2)

does anyone have a idea as to what your rpm's would be on the hwy at
70 m.p.h. running 4.11's as well as 3.73's. with a m6 trans?

ez98ls1

iTrader: (2)

I have 4.11's and my RPM is around 1700 at 70.

rtr2001ss

iTrader: (2)

Keep in mind that the factory tach usually reads 100-150rpm lower than actual.

4.11's in 6th gear @ 70mph should come in at 1800-1900rpm, your cluster might read 1700-1800.

3.73's in 6th @ 70 should come in around 1700 rpm, of course the cluster might read as 1600.

This is given with the average size of tire in the rear which is 25.6" in diameter.

NHRAMAN

iTrader: (1)

3:73 around 1500 or so at 70mph. IN 6TH. MAYBE 1400...Dont really look at that speed though.

rtr2001ss

iTrader: (2)

I used this calc here, it's usually right on. It can also be found in the gear section in a sticky.

http://www.f-body.org/gears/

Just enter tire size, then axel ratio, any top rpm you want, then the gear ratios.

M6 in an F-body as it came is this:
1st: 2.66
2nd: 1.78
3rd: 1.30
4th: 1.0
5th: 0.74
6th: 0.50

Stock 4L60-E:
1st: 3.059
2nd: 1.625
3rd: 1.0
4th: 0.696

TRANS-DAD

iTrader: (1)

4.10'S here w/1800rpm's @ 70mph!

BlackScreaminMachine

iTrader: (17)

Exactly, use the stickies people!

I see about 1800-2000 but again stock tachs are off. If you have a programmer reading the PCM, thats the most accurate, or a aftermarket tach.

alamantia

iTrader: (10)

What are your RPM's at 70 now with your current gears? Did you take algebra in high school?

Darkreign2049

At 72 Mph my tach reads pretty much exactly 2K.