Wheel Size/speed

Does rim size affect acceleration in any way? What's the performance difference between going from 15 inch rims to 18 inch rims? Or is it all just for show? I don't know much about wheels and tires.

[smokinAMD]

Originally posted by bluephoAm@Jul 29 2004, 10:51 AM
Does rim size affect acceleration in any way? What's the performance difference between going from 15 inch rims to 18 inch rims? Or is it all just for show? I don't know much about wheels and tires.

18's are heavier then 15's, so yeah, you'll accelerate a bit slower then before.

[3.4 Euro Alero]

The main issue you have to watch is the overall circumference of the new tire as opposed to the original one. It will determine whether you are actually going faster or slower than your speedometer is showing. I always used to warn people when I sold tires that your average vehicle is usually off aprox. 3 km/h at 100. If you put a tire with a larger circumference, you could actually be going up to 6 or 7 km/h faster than your speedo reads. On the other hand, if the circumference is slightly smaller, you will actually be going slower than you read (it has saved me more than once from radar). Acceleration I do not believe will play much bearing, but hopefully someone who visits the track can comment on that. Good Luck!

[ptrudel]

u'll lose a bit of acceleration because of more weight that has to be turned...that's the downside...on the upside, i noticed that my hwy mpg went up by a bit...close to 4 mpg better...nothing wrong with that...hope this helps a lil :thumbsup:

[3.4 Euro Alero]

Originally posted by 2000_olds_alero@Jul 29 2004, 12:50 PM
i noticed that my hwy mpg went up by a bit...close to 4 mpg better

Definitely a plus, but if you do not work out the proper sizes and your circumference is smaller than it should be, it will use more gas!

Okay, I'll take all of that into consideration when I get around to wheel/tire shopping. Thanks.

Here's a handy little speedo/tire size calculator to figure speedo error with bigger tires:

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

[Sundayalero]

Has anyone with 18s noticed an increased braking distance?

[ptrudel]

Originally posted by Sundayalero@Jul 29 2004, 03:43 PM
Has anyone with 18s noticed an increased braking distance?

harder on the rotors i find...not so bad for breaking distance..i don't think so anyways

[AlbinoMonkeyRat]

bigger rims that are the same weight are good too...it'll reduce the tire weight and help accelleration a little. A safer thing to do (safer in the sense that you are protecting your performance and your speedometer readings) is to get wheels that are the same size, but lighter.

(Just vague knowledge, but it's to the point...)

Like some of those carbon fiber rims.

Another question to extend the discussion:

So a lighter wheel/tire combo will improve performance in all conditions? daily driving, highway driving, drag racing, etc... Or just some?

[smokinAMD]

My new wheels actually weigh a fair amount less then stock wheels, which was a primary reason why I bought those wheels.