E V I L

iTrader: (6)

I am a 1998 Formula and curious on my gas mileage. Mods are: Magnaflow catback (cutout open at times), MTi lid with K&N Filter, LS6 intake with AIR and EGR removed. Wheels are 17x9.5 and 17x11 Heavy ZR1 wheels with 315's in the rear.

Recent tune up consisted of new fuel filter, oil change, seafoam, plugs and wires, new knock sensors and harness.

Also the guy that tuned my car recently finished. I am not quite sure on the extent of what he did but he got rid of my knock and pulled 4 degrees of timing, which I am guessing. But I know it is tuned for 93 gas which I always run.

Car runs EXTREMELY perfect, pulls like crazy and no complaints now that my knock is gone at WOT but right now I am getting somewhere around 170 miles to the tank with ALL CITY DRIVING. I tried calculating my MPG but my numbers always seems off. My Formula is used mainly in the city, all stop and go traffic and i rarely ever see the freeways.

I thought the last step of my full tune up would be new 02 sensors but are my heavy wheels and new performance tune more of my problems than anything? I am just wanting some input. Thanks

98LS-WON

I get 15-17 MPG in town, 28-30 on the highway depending on the speed.

Racer383

my 98 gets 19-21 in town and roughly 25 on highway. I have seen 26 mpg on the highway, but I tend to run a bit hard on longer trips. My mods are not to far off of yours, I have the lid, k&n, ls1 instake, AIR and EGR delete, Magnaflow cat back and the only tuning I changed was to firm up the shifting a bit. I also have 2.73's. WIth the smaller metal tanks that we have, I will see about 260-270 miles to a tank.

keliente

iTrader: (22)

I would probably look over the tune, provided nothing is wrong with the car mechanically.

I do all city driving with 16.5 mpg, and that's with a set of TT's and hauling *** everywhere.

john shea

I'm getting 200 miles to the tank with city highway driving.
I think that's about 13 mpg.

dan00k

iTrader: (1)

i do city driving during the week and hwy on the weekends and have been staying out of the gas some and getting just over 19 combined. on avg., i get about 230-260 out of a tank of gas

bottlefed98

iTrader: (2)

Last time I checked I was getting right at 21 cruising around town and thats with 3.73's,full bolt ons with a whole bunch of timing pulled on stock wheels

bmxer8699

iTrader: (16)

i beat the hell of of my stalled auto with 3.23 gears and get about 170 to the tank.
city driving, and pedal to the floor 50% of the time.

proelky

iTrader: (13)

I'm the same and have a 9" with 4.11's, and H/C setup...still gets 16-18 in town and 23-26 on the hwy.