Wheels and Tires upgrade to 18"

[lemieud]

I currently have a 2001 Boxster with 17" wheels/tires and want to upgrade to 18" wheels/tires, but unsure if any thing else require replacement....such as spindle, rotors, etc and any clearance issue in wheel wells.

Thanks – Dennis

[Jeph]

Depends on the kind of 18" wheels you're getting.
www.wheeldynamics.com is a good source.

[edevlin]

I like my aftermarket 18" carrera lightweight wheels. They give a wider footprint and with lower sidewalls handle better on hard cornering. But one thing you dont hear about that much is what you loose when you move from a 17" to an 18" wheel. Even with my 18" lightweight wheels, they wiegh more than 17" wheels. I could feel the difference in more sluggish acceleration with the 18" wheels as soon as I put them on. Also, the rubber is more expensive on the 18" tires, just mentioning it as a point of information,

Ed

[gregdacat]

Be careful if you change wheel diameters your speedometer might actually start reading the correct speed.

[ekam]

^Also it's because you're putting more tire on the ground which slows it down in exchange for increased traction.

For wheel up-sizing you have to be aware of the appropriate tire size, wheel bolt-pattern, width and offset.

TireRack.com have a lot of great info on wheel/tire upgrade.

http://www.tirerack.com/about/techcenter.jsp

Offset:
http://www.tirerack.com/wheels/tech/techpage.jsp?techid=101

Tire Size Calculator:
http://www.miata.net/garage/tirecalc.html

[RobZ]

FWIW, I upgraded to 18x10 and 18x8.5 about a week after buying my Box. I went through TireRack.com and have once again been very satisfied with the cost, selection, and quick delivery.