Quote Originally Posted by REGs
I'm trying to get some ideas.........

Right now I run a 352 w/ 390 heads, cast iron intake with a holley carb, little lumpy cam (and has PLENTY of power through out the rpm range) & a 3 speed auto trans. in my 1962 Unibody truck.

I'm not sure of the rear gear but I'm running a P295-50-15 tire that is aprox. 26" tall.

At "speed" I'm turning 2800 rpm's (my spedo says 70mph - but that is suspect) or so but it feels like it could use a 4 gear. When I rpm down to 22-2500 it appears that the world is passing me bye.

What "safe" range RPM can I turn this motor to for every day driving??

Any info will be appreciated.

Regs
2800 shouldn't hurt it. i dont like anything over 3200 on a long trip. i have ran as high as 3600, but didn't like it. sound like you might have a 4:10 gear. get behind someone that you know how fast they are going and then you can get a better idea of what you have. a 4 speed won't help your problem, because the 3 and 4 speeds are 1:1 in high gear.