[Berliner Bel Air]

I'm thinking my 283 is working too hard at 60mph at 2200 rpm. The economy is no better than what it was when I had a TH350 in it and it turned at 3000 rpm. The car has 3:73 gears and a 2004R tranny. Summit can special order 4:11's but something even higher would be better, I think. 4:56's or so would put my cruise rpm at around 2600-2700 which would probably be better for economy as well as performance-wise for this little motor. Does anyone produce this gear set for the old 1955 axles?

Off the line the car will not do a burnout, I'm hoping it will be able to with lower gears. But mainly I'm hoping to get better mileage than my friends 57 Chevy with a 2004R, 350 SB which also turns 2200 rpm at 60 mph. Right now both cars get exactly the same mileage, and can accelerate about the same (mine has headers and vortec heads while he runs old unported heads and cast exhaust manifolds). But his car has the higher 'fun factor' I want my Bel Air to be faster and more fuel efficient that his

[techinspector1]

These would be the 2 main hot rod differential guys here in the States in my opinion. Contact them and ask your questions.
http://www.moserengineering.com/
http://www.currieenterprises.com/cestore/home.aspx

[techron]

the third members are the same from 55-64 full size chevys. i have 3 posi units for my racer. one has 4.56, one has 4.88, and one has 5.13 gears. i built these a few years ago but would imagine they would still be available.