I've seen a few people mention that 3.73 is not good for TPI...

Why & how / can this be fixed?

I have 3.08 gears now and the car is not a daily driver...
305 91 Formula TPI 5 Speed

Raf

 

Increasing your gear ratio like that increases the operating RMP's of your motor. TPI is not a high reving induction and does not make power in the upper powerband. Therfore, adding gears that will make your motor run more in that low power area will slow you down. I am pretty sure that guys don't see much track improvement when they go from 3.42's to 3.73's on a stock TPI.

 

Ok... so Hooker 2055's, magnaflow 3 inch Cat & Super 40 Flowmaster for exhaust side...

Intake, ported plenum, Accel Runners & Accel Base...

Only bottleneck left is stock heads...

So 3.42 is still better choice ?

Raf

 

Actually your bottely neck will always be the stock TPI no matter how muhc your port it. None the less, what you have planned will be great improvements. I would stick with the 3.42's until you have a cam swap with head work and anther form of induction. You may want to ask the TPI guys if they ran faster with 3.73's.

 

I had 3.08 posi before ...now I got the 3.73's in there. It makes for a fun light to light burner. SOme have gained a half second in the 1/4 going from 3.08 to 3.73. I myself like them alot. Your first gear is dam short though . If you are trying to make the most optimal setup ....go with the 3.42.