I am considering putting 18 inch rims on my Z28. My question is whether or not it will slow me down, (meaning affect my quarter mile times, 0-60, etc...). Or should I consider only going up to a 17 inch rim. I hate to have to slow the car down just so I can have nicer rims.
Thanks!

 

It could slow you down slightly... nothing dramatic.

What will make a major difference is your tire composition, so I would worry more about what tires you are going to use at the track.

If you are talking about street racing, I wouldn't worry about it AT ALL

 

Anything that moves the weight (in this case the tire and bead part of the rim) further from the axle increases the HP absorbed (= lost) in bringing the rotating mass up to speed. And, if you are actually running at the track, you will not have much of a choice in truely "sticky" tires... I think the Nitto 18" drag radials will not be out until the end of the year. And, the thin sidewall works agains "1/4-mile" traction.

You have to decide the priorities for your car... looking good, being only slightly disadvantaged on the street, or being completely on the wrong size wheels at the track. If you seldom go to the track, or if you do go a lot and can afford a dedicated set of drag wheels and tires, the 18's won't hurt you that much. It will also prolong the life of the very expensive 18" tires if they don't see a lot of track use.

 

Why not get what you want and throw the old rims on (with DOTs or slicks) for the track? My friends do this all the time.

Best of both worlds.

 

EXACTLY...

 

Thanks a lot! I think I will consider keeping my rims which currently have nittos on them for use at the track.

Injuneer,
I was wondering if you could elaborate on what you mean about the thin side wall working againt 1/4 mile traction? I am not to well educated on the dynamics of tire composition.

Thanks Again!

 

Well, simply put have you ever seen a Top Fueler? They have a huge sidewall. That sidewall flexes upon launch allowing for faster launches. Because the flex in the sidewall allows for the tire to get traction very fast.

Because a thin sidewall really can't flex, the tire will spin on the driving surface until it can grip the road.

I think that is the layman's answer.

 

17's wont make your car go any quicker...

 

??? over 18's? from a dead stop? yes they will. 16's woudl be perfect (any smaller and you need to "trim" the brake calipers to fit inside)