rear end problem
 

Hey guys I have a 7.75 inch rear end with 3:45 in my 1979....I am currently rebuilding the engine....upgrades as it stands are basic and include...4 barrel intake and Edelbrock 600 carb, Competition Cam setup with an E303 I think, a 42 psi edelbrock fuel pump, Fllow master headers and H-pipe...under drive pullies and a new alt are coming...I know this doesn't sound all that wonderful compared to some of your setups but I was wondering if my 3:45 will hold up to whatever power the engine puts out?

Sounds like 3.45 gears would be a decent ratio for your setup, if it will be for street use that is. You will still have decent gas mileage and top speed while gaining acceleration on the low end.

7.75 or 7.5? I thought there was a 6.75 and a 7.5?

The 6.75 will get trashed. The 7.5 might hold 250hp or so.

The 7.5 should hold up fine on the street, with street tires, but if you go to the track and put on some drag radials or slicks and use high rpm launches you'll have problems. I ran my 7.5 with the 3.45's in it for a long time.