I get around 27 and I am in the turbo all the time. I say that something's up buddy.

 

i got a 99 gs w/ intake and exhaust only and i get apx 320miles per tank... and that's mostly city driving.

 

I have a 97 gsx and I get about 200 miles per tank.. It seems that I am not the only one to experience low gas milage.. Also my coworker has a 96 gsx and we get about the same fuel economy. I am thinking something is also worng after hearing this thread!!

 

Got over 400 one time... no joke. Driving back from picking the car up ...drove at like 3k for about 350 miles and got home with half a tank. 1996 GST @ 15psi

 

I've heard a lot of things can cause bad gas mileage. Bad 02 sensors, air filter, even a bad wheel alignment can cause your gas to go down a bit. I have an 01 GT, put $20 of 89 and got about 80 highway miles till it was empty again. 89 octane is $2.89 today.

 

I get great gas milage, but my car is sitting at home while I am in Iraq so at least I don't have to buy gas for a while lol

 

Gas here in Vegas for 91 grade is $3.30 and 100 octane is $5.. I think i will run 100 octance soon if that stays the same...lol Also is 100 octane good for the GSX.. I know i put 6 gallons or close to 1/2 a tank and my fuel economy was actually a little better and the ran AWESOME!!

 

i have a 97 gst spyder and i get about 300 miles on a tank of 93 octane. I have some mods tho so that might bring it down a lil. Something is def. wrong, even if you did a tune up i still dont think it would make up that much difference.

 

also driving w/ the window's down will cause you to have worse gas mileage... but my windows HAVE to be down lol

 

higher octane will make cars run better i got a 90 eclipse gs thats 5 spd i get about 250 to 300 miles