1991 Camaro rs TBI has flowmaster muffeler with elderbrock high flow car and a cut-out. If i put 3:73 gear ratio in the rear end will i feel a difference? will it help me gain horsepower or make it jump off the line quick? will it be faster?
Thanks

 

yes, no, yes, yes, in that order.

 

To be clear on that last yes. It will accelerate faster but not have quite as high a top speed for the same rpm.

 

Im thinking about swapping gearing, how low can i go with having a top speed of 85+ with a th350 (3 speed auto) tranny? 4:11 too low??

 

Depends on how much power your engine makes at whatever RPM that will force it to turn at, at that speed.

If it's a stock LG4 (the only 305 4-bbl in 87), it probably won't even go 85 set up like that. Or if it does it will take it about half an hour to get there.

 

With a TH350 and 26" tires, a 3.73:1 gear will need at least 4300 rpm to go 85 MPH. That's insane. The typical LG4 only needs 2100 rpm to do 85 MPH. You might get 13 MPG, probably less.

 

I changed from a 2.73,open rear to a 3.42 and Eaton posi. and noticed a considerable amount of change. Much nicer off the line . The best upgrade so far. If your going to do the gear change be sure to add a posi. while your in there. I suggest the Eaton.