A 275/60R15 tire has a 28” diameter.
So a 0.86 OD gear with a 28” tall tire and 3.55 rear axle will give you RPMs of 2381 at 65MPH.
A 700R4 has a 0.70 OD gear according to the internet. If your 350 SBC is as strong as it sounds, your engine should have plenty of power to use it effectively. A 0.70 OD gear X 3.55 rear axle with a 28” tall tire at 65 MPH will have RPMs at 1938.
Last edited by Lugnutz; 10/31/2021 6:55 PM.
