SBR291

Hey if anyone can help me, ive tried searching but cant find an answer, well I have the 18x8.5 aspec wheels for acura of course, they came with Michelin Pilot Sport A/S Plus 245/40 18, after install i notice my gas mileage went down from 28 to 26 why is that, i used to have type s rims with michillen pilot MXH MX4M tires 235/45 17

Does the tire size have something to do with gas mileage?

Does rims size have to do with gas?

princelybug

iTrader: (16)

Larger rims usually mean more weight, which is detrimental to fuel mileage.

Also, your larger rims require larger tires, which means more weight, which is detrimental to fuel mileage.

Just for your FYI, the 18x8.5 A-Spec wheels came with 235/40VR18 Yokohama AVS ES100 tires from the factory.

Turbonut

iTrader: (1)

Not only the weight, but the tire design will affect fuel mileage.
Some reading:
http://www.tirerack.com/tires/tirete....jsp?techid=29
http://www.tirerack.com/tires/tirete...jsp?techid=175

SBR291

thanks guys.. and for tires i bought these off a guy who got his car totaled before he could install. he had these tires installed when i got them brand new 245/40 18 michilen pilot sport plus tires. but i want to go with continental DWS All season 235/40ZR/18s

I hate cars

That size difference would be pretty much undetectable in mpg. I went from a 235 to a 255 and it might have made .5mpg only on the freeway but .5 is pretty much in the margin of test error. I felt a larger difference especially in coasting when I got rid of the OEM tires the first time.