i notice most you turbo guys are getting pretty good gas mileage, i can only get a about 240 a full tank cruising the whole tank i notice some of you turbo guys get better gas mileage than when ya were all motor, i dont see why im getting bad on a stock turbo ls

 

All in how good your tuner is man
what afr's are you showing while cruising. I see around 14.4-15.1

 

you may have the wrong tune. If your running rich then you could be wasting a lot of gas.

 

Its all in the tune. I get about 32mpg driving normal and about 25mpg boosting a good amount in a stroked gsr about 400whp

 

Yep. Definitely in the tune and how much you use that right foot. I'm 30-32 mpg with regular country road and town driving. 40-45 mpg highway. GSR trans, Precision 880cc's, 1.8L, GSR cams, 92-93 octane, 2350 lbs, tuned by John Kerr of J-K-Tuning / Innovative Motorworks.

Via NepTune's wideband targeting, car cruises around at 13.8 - 14.8 AFR. Idles anywhere from 12.0 - 15.5 depending on engine temp. Sometimes it'll spike out to the 16:1 at idle randomly. Basically, make sure you aren't cruising in the 11 or 12s. :p

 

thanks for all the great info, but this is weird i get good gas mileage city wise only but on highway its like the worst of worst ever and thats just cruising 60

 

Sounds to me your tuner tuned boost and moderate load (low vacuum, light accerlaration), but not the cruising/med load cells. Some people will be lazy and not tune partial throttle all that well. Combine that with disabling your oxygen sensor, and you're at the mercy of a potentially bad tune.