Pinto Car Club of America

Just finished...(OK, it'll never be finished) with a V8 swap, 302/C4. Took a ride down the highway, still have the original rearend, and my rpm's were 3k at 55mph. Looking for a 8" posi that will let me do 75-80mph at 3k. The rear wheels are 15x7 with 225/60/15 tires. I want a highway cruiser for pulling my bike to ralleys, not dragracer. What do recommend?

a truck! ;D   3:08 to 3:25 or so should work for you and still give you a bit of decent acceleration, go into 2:something , its gonna really feel like a dog off the line.

I think 3.00 gears in the 8'" rear will have you running about 3300 rpm at 75 with a stock converter.  Since you already have a 302, and are not interested in blazing acceleration, you would probably be happier with something around 2.73.
I based my rpm estimate on my car's old combination.  I ran 2300 at 55 with 3.00 gears, 4 speed, and about the same size tires you have.  That works out to about 3140 at 75, and figure about 200 more rpm for converter slippage.
By the way, what do you have in the rear now?  Must be around 3.73.

for comparison, I was taching out at 3000 rpm at 70mph with 185/70-13 tires and a 2:73 rear.

 8)a 3.00 gear will have your pinto crusing at 75 and turning 3k rpm. since the car is light, and the 302 makes good torque a 3.00 gear is all you need for what you want.