mazdasezoom

Hello all I finally decided to upgrade my wheels. Currently I have the 13inch steel wheels (yea I know). I'm planning on getting 15-inch rims MS Type 3, 15in from cork sport. The only concern I have is how this is going to affect my ride what are the disadvantage & advantages in getting bigger rims?

greenlantern94

If you change the overall size of the wheel, your acceleration and milage are going to decrease. By overall size I mean diameter including wheel+tire. Also, your speedometer is going to be incorrect. If you wanna keep the same overall diameter and get 15's, you're gonna need real low profile tires.

I've never changed my wheels, i'm just going by physics.

mike323

The size of the wheel won't impact acceleration not gas mileage, it's the total weight that will make an impact, and the impact is very minimal.

If he goes with 195/50/15 tires his speedometer readings will be about 0.3% less(therefore his speedo will read 60mph and he's actually going 59.8mph), and with 205/50/15 tires it's going to be about 1.3% more(60.75mph instead of 60mph). This is negligle since no speedometer in any car is accurate therefore choose the two size above.

limpgtx

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

greenlantern94

if you had read what i said, i said the OVERALL diameter of the wheel and the tire together, if changed, will affect his acceleration and milage. it's simple physics, because now the same engine has to make more revolutions to get the larger wheels to make one revolution.

mike323

The wheel has nothing to do with revolution/mile, it's the outer diameter of the tires.

greenlantern94

that's what i was talking about all along, sorry if i misunderstood you.