DISREGARD, I just found the thread on this... Sorry for the needless post....

67 Stock SS 350 with Muncie 4 speed and 12 bolt posi. What is the best all-around differential gear ratio for car? The restoration is to stock and will be a trailer queen with occasional road trips. Looking for reasonable power without killing gas mileage terribly.

Thanks..

 

Gear selection is about what you want or even the terrain were you live. When I lived in South Carolina even thing was flat and wide open. In West Virginia finding and strait roar other then an interstate was tuff.

I like the stock 3:55. Just keep in mind that tire diameter had as much effect as rear gear. If you know the diameter and can calculate a final drive. Even car has a 1:1 ratio gear (non-overdrive) So you could test cars and find on you like then get the same final drive. This would verify your cruising speed and top end limits.

 

Thanks. I finally opened up the differential and it is currently a 3.31. The gears look good and as near as I can tell so does the backlash. The pinion seal needs to be replaced so I think I will just replace that and the axle wheel bearings for now. Budget constraints...