Advice on the gear ratio for 350 vortec with TH350 -

[albertan82]

Hi ,

I have a 1964 C10 Stepside - short wheelbase, with 350 5.7 vortec and TH350. Tires are 225/75R15 (28.5").

Current differential is from a 1973 Chevrolet Caprice (350 engine) added to the truck by the previous owner, but I do not know the current gear ratio. It is the 10 bolt, 8.5", 28 spline differential.

When I drive on the highway at 60mph, tach is showing around 4000rpm (

What gear ratio would be the best for this engine-trans-tire combo?

Thank you all in advance


From:
Istanbul, Turkey