I was jsut wondering what u guys think a 89 iroc z with the l98, a 2500 stall, apfr set at about 48psi(not yet installed), 12* advance timing,.62 tps volts, and a 3" dynomax exhaust should get on gas. Around town and highway. Also, im kinda confused on the torque converter would it be a better gas saver if i have it in drive or overdrive? which does it lock-up in? Also, my reg fuel pressure regulator is almost shot and i have the option of getting the stock one new for 30 bucks. I was wondering if it is worth the 15-20 bucks more for the afpr? Is it worth the gains people say it is if set reasoably? And how much would it set around 48 psi effect gas? Thanks a hell of a lot!

 

Im hoping for 15/20 what u guys think

 

Your torque converter should lock in both 3rd and 4rth gears.
I think you should get around 26 to 28 MPG on the highway @60mph.

 

I've got 273 open, and at 55 mph I'm taching 1500

 

The TQ actually locks up in 2nd also, if it gets time to. Putt in second and hold light throttle for a while. You'll feel it.

Anywho, you will actually get better MPG with the mods you described, but ONLY if you can keep your foot out of it.