I was strongly contemplating getting a set of the Kosei K1 TS wheels:

Kosei K-1 TS

but tirerack says spacers are required. Should I care about this? I vaguely remember that there was some reason that spacers were bad.

 

they wear out wheel bearings faster than normal.
Thats all I can think of...

 

spacers adding weight?!?!

 

how big of a spacer is needed? If its relatively small (under 5mm), you should be fine. Any bigger and I would look into the H&R style which have integrated studs, to ensure you have enough thread to still hold the wheel on

 

This idea of spacers wearing out the bearings more quickly is misleading IMO. All a spacer does is put the tire farther away from the hub - and if you're going to a wheel that allows the inner tread block to be located farther away from the centerpoint of the car, then yes, you will create more stress on the suspension, in proportion to the thickness of the spacer. However, if your goal of the spacer is to allow a wider wheel that has a more attractive profile relationship to the quarterpanel (offset) but keeps the inner tread in the same position, or even more inbound, then there is no worry. Keep in mind, a grippier tire creates as large a variable on increased suspension stress as any spacer anyone with a Z would employ. (unless of course you go with 14" rims put entirely outside the body of the car, in which case you should be shot, hehe).

 

so what is the largest size spacer on the rear you can run (on a stock rim) without rolling the fenders? 20mm?

 

Beats me. It depends upon your starting point (your rim). On a 19x10 Racing Hart J8 with a 275 series tire, it is 19mm offset, so you'll have to do the adjusting math on your side.

 

i said on a stock rim

 

which stock rim? 17", 18" or 18" rays? I assume not the anniversary rim?

 

Assuming the studs are the same length between the Z and the G - I would say a 3mm spacer is max. I'm running a 3mm spacer for my winter rims (stock G35 coupe 17's) and get 7-8 turns instead of 10 without the spacer. Those numbers are before torquing, of course. If I were getting less than 7 turns, I'd have to suggest getting longer studs... So 3mm max.

Mike

 

I run 25mm bolt-on rear spacers with stock rims.

No clearance issues.

I posted pics of comparison in an old thread (about 1 year old). If you search spacers and my name you should find it.

In fact, my sig has a picture of me running the 25mm spacers in the rear.