Tire-width has nothing to do with the operation of traction-control. So long as the tires are properly sized in terms of diameter (as close to stock as possible), there is no reason for anything to malfunction.

Pretty much holding up the track newby sign here. Thanks!

Because you are using these as track tires with the VDC turned off I wouldn't worry about it too much. The size differential is really only a problem for the traction control, with it disabled it doesn't intervene until the speed difference between front and rear is huge.

For daily driver tires you want the size differential as close as possible, within 2% front to rear.

With the R888 sizes listed your differential front to rear will be 2.3%.

If you're a track newbie, why switch tires? The stock tires hold up pretty decently and have great grip for street tires. I think, and I've heard it said by others, that you learn a lot more about proper car control without the crutch of ultra-sticky tires. They prevent you from exploring the limits from seeing your mistakes as easily. Just a thought...

One other benefit: track tires are just going to cause more brake issues, fuel starvation issues, etc., which isn't much fun...

The isn't exactly true. The tire diameter difference effects your ABS which cannot be turned off. The computer might turn it off if it detects an issue; then again, it could just damage your abs system. You are correct tat 2% difference in diameter front to rear should be acceptable for the ABS system.

I agree, kind of. Track tires don't make a lot of noise when they are about to give way, and when they do break loose, they do it in a very quick fashion, where as street tires make some noise and let you know you are approaching the limits and are a little more forgiving. I would do at least 5 events on streets before upgrading.

As for tire selection, I was using used R888s, but they just didn't last too well. I have since switched to BFG R1s and love them. A little less grip than a hoosier, but not enough less to justify the extra cost of the hoosiers. I run 275/35-18 all around myself.

Okay, there are tons of options for 18" wheels, but what are the options for R-Comps on stock wheels? I'm having a hard time finding tires....

Hoosier R6's are one of the few that I found when researching. That's why I decided to buy 18" track wheels.

The ABS should be handle even more than 2% theoretically, perhaps 4 or 5%. Unfortunately discovering it's true thresholds would require insider knowledge of it's workings or lots of empirical testing.

If you want R-comps and still want to drive to the track with them, then the Nitto NT-01 can't be beat. They don't stick quite as well as the (100 wear rating vs ~40 for stickier R-comps) best, but they come close, are cheaper, wear nearly as well as a 'normal UHP' tire...and can be driven to track. I've had two sets and overall would give their performance a B+ compared to an A for my current BFG R1s capabilities. An experienced track junkie can certainly tell the difference on track plumbing the limits of adhesion, but someone new to R-comps will be suitably impressed.

The bigger jump by far is from ANY UHP tire to the R-comp, in this case the NT-01 being the case in point. These simply have different and generally better grip, breakaway, and recovery characteristics. You won't be disappointed coming from a street tire!

I've done as much as 400 miles highway on them at a go with no problems...they actually have a decent comfy ride and (of course) handle amazingly! At first I was worried about using them on the highway and such, but have no such worry, they're fine... and talk about serious street grip!

The only thing to watch out for is in the second half of their useful life there is no tread, and you need to be careful in the rain. First half they have decent tread and are fine, not a rain tire, but the 6/32 of tread will keep you out of trouble. Once you're down to 3/32 (the 'racing slick' half of their life), all rain bets are off. I did have to drive them in slick mode once a few hundred miles in the rain and it wasn't too bad as long you keep speed <60mph and you're really really careful, and it's just not really a downpour. But that's nothing I would want to do if I had a choice.

PS the NT-05 are awesome too. I've got them as my street tire and they 'feel' very much like the NT-01, minus the r-comp tire noise. That's a street opinion only... so although they feel track worthy, I've not used them on track, prefering the R1s obviously. Those four R1s fit nicely in the back seat of my Rx-8, so I've got the best of street tire on the way to track, and some of the best track tires while I'm there! :driving:

R888's are my choice.