supapoopa

Anyone notice a big difference in their fuel consumption when 1+ their wheel size. Would like to go up to 16x7 but i have to commute quite a bit, and with gas prices going up just wanted to read about others experiences. I'm currently on 15" teg wheels and was just going to get another set of 15's but figured it wouldn't be that much more to upgrade to 16".

Just having trouble deciding between 15x6.5 and 16x7. Also what wheel and tire combo would get me closest to stock diameter. The 15's I am currently on have 205/50's on them and I notice that over 60 mph the speed difference between what speedo and actual is almost 5+ mph difference. Would the 16's with 45 or 40's be a better match to get me closer to stock then the current 15's i have?

Sorry for the long post.

CivicSiRacer

You will always get better mpg with a ligher wheel and tire. MOst of the time when you plus size the wheel AND tire get heavier which takes more energy/fuel to turn.

I know my 16x7.5" Kosei K1s with Azenis were about 42lbs. My 15x7" Kosei K1s with Azenis were 34lbs.

monicle

not exactly true. If you somehow ran an 11" wheel as opposed to a 15" wheel you would lose gas mileage even though they are lighter. if you set gear ratios aside 1 revolution of the motor would equal 1 revolution of the tires. a larger wheel would take you farther per each revolution. (didnt anyone else build mousetrap cars back in elementary school?) The weight part however will slightly effect mileage if you were comparing wheels of the same size. as long as youre not going from a stock wheel to a 25lb bohemoth (spelling) you wont notice much difference at all.
I went from hx wheels to 17" enkei rs6 (20lbs a piece per rim) and the change wasnt noticeable.

supapoopa

Well what about the wheel size and tire size just for highway cruising. I know the current 15" 205/50's are slightly smaller in diameter compared to stock. I notice it with just the relation of RPM's to Speedo MPH. With the stock setup i would be around 3400 RPM at 70 MPH, now its 4000 RPM for when I am going 70. If i were to switch to 16x7's is there a better tire size that would get me close, if not slightly over, the stock diameter. I know doing this would be like increasing the final drive and make me even slower, but i'm guessing i would at least get better cruising MPG. That is, if the ideal 16" wheel tire combo is at least what the stock diameter would be, RIght?


I have quite a long commute and the fact that the gearing is shorter with the smaller overall diameter, its really starting to rack up the mileage since the odo is measuring 'shorter miles.'

CivicSiRacer

I was figuring the fact the the wheel/tire is the same as stock. Also wider tires will suck gas more of course because you have more rolling resistance.

supapoopa

Posted at the same time.

CivicSiRacer: Can you please tell me what you think the ideal wheel/tire size for 16x7's would be for a 96-00 civic ex? Do you know what the stock diameter is and what the 16x7 wheel with tire diameter would be.

ahkeen

i too have notice a huge difference in mpg when u plus size the rims/tires. my 95 civic dx (13in stock) and i went up to 17in and i actually have to fill up more often and i have to gas it a bit more than usual on highway cruising. Im thinking of going down to lighter and smaller size wheels, 15in 5zigen Fn01r-c with proxes 4

CivicSiRacer

holy schnit back from the dead.

ahkeen

sry if i brought this back from the dead.

TheJGB3

Here are the overall diameters for 96-00 Civics
EX - stock size 185/65R14 23.39453inches
SI - stock size 195/55R15 23.37890inches (also called a +1 fitment) +1 inch rim size
Honda Fit 2006-7 optional size 205/45R16 23.20703 (+2 fitment) to the OE EX size
Honda Prelude 97-01 OE size 205/50R16 24.0071 (+2 fitment) to the OE EX size

Here is a tire size calulator (JAVA runtime is required for it to work)
http://www.miata.net/garage/tirecalc.html