Rim Size?

[civ02si]

I'm taking my 18" rims off and replacing them with 16" rims in the morning. How is this going to effect the acceleration of my car and launch with more rubber around the rim.

[NuG]

you'll notice a huge difference between the two. You'll be able to take off quicker and brake quicker because of the weight difference

also check http://www.miata.net/garage/tirecalc.html
and you can see how much difference in diameter you'll be going from

[BarracksSi]

If you size your tires correctly, you wouldn't have any speedometer errors or things like that. Having said that,

lighter wheels = faster-spinning wheels;
wheels with most of their mass pushed to the outside (as in big rims with short sidewalls) = slower-accelerating wheels.

Track cars have big rims for shorter sidewalls (crisper handling) and to make room for big brakes.

Drag cars have small, light rims with deep sidewalls for lower mass and a bigger contact patch. Drop the tire pressure a bit, and when the torque distorts the tire's shape, you'll have more rubber pulling on the track.

[shimmy_yaz]

When I took my 18's off for the winter and put my stock 15's back on I couldn't believe the power change I noticed.