The v6 should be capable of high 20's on the highway easy. Didn't teh V6's have 2 different gearing options available (depening on other options?)? Pretty sure you can find out through your RPO code.

 

Yeah Liberty has mentioned it and referenced it a bunch of times. Here are some RPO codes:

http://www.mafia-motorsports.com/for...rpo_codes.html

GU4 is 3.08 gears
GU5 is 3.23
GU6 = 3.42

 

Your car is EPA rated for 29-30 MPG. You will not do so well in the mountains. But it is doable if you drive sane. I have never owned car that that could not hit EPA numbers or better. If you can not hit that something is wrong with your car. If you where getting 26-27 highway would would say you where just a little hvy footed. Is your car up todate with maintenance? Plugs/wires all the filters? When where the O2 sensors replaced last?

Headers and free flowing exhaust can help mileage as long as you keep your foot out of it, Same with the CAI. If you start messing with the cams and heads to gain power then you will do more damage to your mileage then the 3.73 gears will do. Anything that will raise your power bands RPM will do so at the cost of low RPMs power. If you motor has less power at low RPM (aka crusing speed) you mileage will drop.

 

what? what are you talking about mine gets an EPA of like 26? and thats highway hahaha, city is 17? where are you getting these numbers?????? are you talking about the 1998 3.8 v6?????????

http://www.fueleconomy.gov/feg/bymod...t_Camaro.shtml

 

Those are the revised numbers. When you car was sold new it was it was listed as 17-29 MPG. The goverment changed the standards to take into account Hills and extreme cold and hot. On a normal day without major hills you should be able to hit the original numbers.