PDA

View Full Version : Handling Mods Gas Mileage Affected?


Brett
04-16-2007, 12:15 PM
Just curious, would going up from the factory wheel (17") to a 20" affect my gas mileage? I may be paranoid but it seems like my mileage has gone down a bit since changing to the bigger (Heavier) size.
The Yousef
04-16-2007, 12:19 PM
yes...heavier wheel means more rotational mass means decreased gas mileage...also means you are going to wear out brakes sooner...
Kyle
04-16-2007, 12:21 PM
Yeah I would expect it to. Heavier wheel and its circumfrence is bigger.
william_jeff
04-16-2007, 12:39 PM
bigger diameter+heavier wheel=worse gas mileage

you selling the factories?
Brett
04-16-2007, 12:43 PM
Well what kind of BS is that? lol.

And brakes are over rated so I dont need those...LOL

I was going to sell the factory wheels, But I am going to keep them I think due to god forbid I mess up a rim I have a back up set to roll on.
LeX
04-16-2007, 02:46 PM
around town it definitely matters.... if you do a ton of highway driving like me you hardly notice it... once they are rotating then physics just does its stuff and i hardly notice a difference
Spyder
04-16-2007, 03:07 PM
yes...heavier wheel means more rotational mass means decreased gas mileage...also means you are going to wear out brakes sooner...


Corrected.
Spyder
04-16-2007, 03:10 PM
Basically all of this is true...... unless you have a diesel in which case having a larger wheel and tire (over all dimensions) will create a slight strain increase on the engine but will create a much lower operating RPM at a given speed and there for increase the over all fuel economy by a great deal in some cases... the reason I site Diesels directly is because they react alot more to a 300rpm difference then a gasoline motor in terms of fuel consumption.
The Yousef
04-16-2007, 03:24 PM
Corrected.
damnit...proofreading ftl!

thanks...
Nittanys1
04-16-2007, 03:27 PM
Yousef hit the nail on the head!
an0therh22
04-17-2007, 07:32 PM
bigger wheels will also throw your odometer off too.
Nittanys1
04-17-2007, 07:34 PM
not true....

If you compensate the tire size you can have accurate readings....

Time to go back to schoool!!

http://www.miata.net/garage/tirecalc.html
an0therh22
04-18-2007, 06:47 AM
dam it and i stand here owned. thanks for the correction nittany.
an0therh22
04-18-2007, 06:48 AM
tried to prop u but i have to wait 24 hours
Spyder
04-18-2007, 08:29 AM
not true....

If you compensate the tire size you can have accurate readings....

Time to go back to schoool!!

http://www.miata.net/garage/tirecalc.html

That is correct, unfortunatly not very often does it work out to have the size tire they recommend on a car... its all about maintaining the proper circumfirence. however this only helps the speedo and odo... the gas mileage and hangling will be affected reguardless because of a change in the placement of weight... and the fact you just added a ton of unsprung weight.
speedminded
04-24-2007, 01:42 PM
^^^^ What they said basically. You always want to keep as close to the original outside diameter as you can. You go up a wheel size then you go down a series in tires.

hey bert, enter the before and after info in this calculator and post up the results... http://www.miata.net/garage/tirecalc.html