Gear Ratio and RPM deciding on gears

Rule of thumb for street performance is multiply the tach by two. 3000 @ 60 is what many cars were for the street .. My 70 RR with a 354 Dana 4spd and 275 60's was 3000 @ 60 It was a good driver and still quite quick. I can remember the tach and speedo were both straight up at 60 in 4th



I would say tire size should be your first choice. You can by and sell gears easier then you can sell used tires when their hanging on the quarters. LOL