My 64 had a 350 put in it. It still has the stock (3.08) gears and rearend. I dont think that the stock rear end is letting me use the 350 to its full potential especially, off the line where i just spin the heck out of my tires andstand still.

I want to know what i should get posi, locker, gears. To put in my rear end.

Its a 350, heavy cam, rpm intake, its putting out close to if not a little over 400 HP. I have a 14 inch rims.

ok

What are the specs on the cam? Is it "heavy" as in one for a heavy vehicle that needs torque, or "heavy" as in one with gobs of lift and duration? (Heavy is kind of a relative term - racers would call a .520 lift cam mild, but for a street car it's stout.)

How tall are your rear tires?
Will you be using slicks at the track?
Do you have a stick trans or auto?

You're gonna want to tailor the rear gear towards your cam, so, again, the specs on that are important.

If you're not concerned with getting the absolut max out of the whole deal, a decent upgrade would be a 3.42 or 3.55 gear.

Keep in mind, as the gear ratio number goes up, your RPMs at cruising speed will rise as well. If you put in very tall gears you will be racing the engine RPMs on the highway when going 55mph.

Hope this helps.