Smokin 500HP Club
Join Date: Jan 2007
Location: Gladstone (Kansas City) Missouri
Rough numbers here, but a 3.70 gear, you can figure on 3500 RPM being right about 70 MPH. That's with a 1:1 final trans gear (TH350 in 3rd) There are a bunch of calculators out there to help figure speed/RPM/gear ratio.
Like fishslayer pointed out- 3.55's are a pretty good all around gear.
I'm running 4:11's, crap on the highway, but a blast around town. I'd like to have 3.08's but I'm making the HP/TQ to pull them with a BB. Won't help much with mileage in my case either. Ol' Red drinks gas nearly as fast as I do Jack Daniels'.