90BlackGTA

iTrader: (1)

My car is all stock and is my daily driver. I will eventually do some light mods but nothing too serious. I hear gas mileage isn't too bad with 3.73's with OD but some people say 3.73's don't respond well with the 350TPI? This is also a street car only. What do you guys think.. thanks.

antman89iroc

When my car was mostly stock (TPI small cam etc) I had 2.73's, 3.70's and 3.27. The car ran about the same 1/8 mile times with the 3.70's and the 3.27's. I stayed with the 3.27's since they're a lot better for everyday drivine. With 3.70's and an automatic the car would shift to second in about ten feet (seriously) so it seemed about the same cause the trans was always in a higher gear. Now that I have done more mods to the engine (heads, HSR, headers etc) and run a five speed, the 3.27's are about perfect. I would probably go with 3.45's (I have a 9 bolt) if I made a change now.

90BlackGTA

iTrader: (1)

Yeah i'm thinking of going with 3.42's...3.73's seem like too much for my stock GTA and i'm afraid I won't have any traction from a start...also I hear 3.73's don't work well with the 350TPI, so it seems i'm better off with 3.42's and i'll still get good gas mileage...

89IrocZ350TPI

3.45 gears are the best for the 350TPI IMO. My 1/4 went from 13.8 to 13.3.

antman89iroc

Oh yeah I forgot, even with 3.27's first gear is still pretty usless under high loads. Too much tire spin- especially on the street. At the drags I get excellent traction if I don't over-rev the launch. But with 3.70's forget it. Traction was very limited.

89IrocZ350TPI

3.7X is just too much gear for a stock TPI setup, and its even a bit much for a heavily ported TPI. If you plan on getting a HSR Id say 3.73's-3.90's but for TPI 3.4X is your best bet.

90BlackGTA

iTrader: (1)

Alright its final! I called him and went with 3.42's!