Quote Originally Posted by petrified.rabbit
the 17's with tires would distort these numbers also...

i am not going to go look up the math but i think a 205/40r17 is like an inch more diameter than stock.
which means every revolution of the wheel you are traveling like 3.14 inches further.. which means when your stock speedo says you are going 65 mph you are actually travelling 67 mph.. but it also works like that for the odometer.

for good gas mileage changes get the lightest wheel and tire set up you can.. i think konig daylite or feathers are cheap and like 11-13 lbs.. most of the time a 17" wheel and tire weigh more than the stock 14. which costs you in gas mileage. also if you go bigger that stock rolling diameter you will travel further for the same amount of gas.. but it wouldn't show in your numbers..

if you can find a tune with fuel cut out that will help tremendously on gas savings. (cuts fuel on deceleration) but i doubt that is available since no chips are out for the aveo..

i saw a 20 mile per tank jump when i put lowering springs on.. but i think it was more of a break in, that aerodynamics change.

im runnin 205/35/r17 so it was a lil bit closer and also i was runnin the stockers up front with the wider wheels on the back.

edit: just read my post and saw how it is confusing. currently i have my 17s all around, at the time tho i only had the stockers up front. sorry ::embarrassed::