Street or R-Compound Tires? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

j.fro · 10-01-2011, 04:45 AM

+1
"If you want to be competitive in a stock class you need to run R-compounds. (hoosiers or 710's are by far the best)..."

Topless · 10-01-2011, 04:40 PM

As I understand it Thstone is a track guy looking for a good track tire. He doesn't do SCCA Solo at all. Different game, different rules, different tools. YMMV

jsceash · 10-02-2011, 06:24 PM

Have you tried something like the Hankook RS3. Still a street tire has a 140 tread wear and a pretty solid block patern. My last Instructor recommend these as a step before the R compounds. His reason was they will still howl a little before they break loose. R's are likely to break loose with no notice and at track speed that, well.

thstone · 10-03-2011, 10:22 PM

Thanks for all of the great advice! I meant to post back over the weekend but was busy changing out the pads/rotors and oil/filter.

I'm already running EBC Redstuff brake pads that seem to work pretty well for street and track and I've had the brake fluid changed to a high temp type suitable for track use.

Back to the tires, I'm running Kumho Ecsta XS now (180 treadwear) and they might last 2-3 more track days (or through the end of this month) so I need to make a decision pretty soon and get whatever I'm going to use in November on order.

Right now, I am leaning towards buying one more set of street tires and then move to the R-comp's early next year. By then, the spec boxster series should have selected a new spec tire which will probably influence my selection (as I would like to end up in BSX eventually).

I will look into the Hankook RS-3...

jsceash · 10-04-2011, 08:09 PM

I'm going to run them the first time in a DE @ WGI NY, next week I'll tell you how they run compaired the Pilot sport Cup which were 180 also I have an 03 boxster and I'm running 18X8 with 225-40ZR 18 Fronts and 18X9 with 265-35ZR18 rears.

jsceash · 10-04-2011, 08:19 PM

I didn't say this before they are well under a grand for a set new and the PS Cups were $1300+

MikenOH · 10-05-2011, 10:05 AM

Quote:

Originally Posted by thstone

Thanks for all of the great advice! I meant to post back over the weekend but was busy changing out the pads/rotors and oil/filter.

I'm already running EBC Redstuff brake pads that seem to work pretty well for street and track and I've had the brake fluid changed to a high temp type suitable for track use.

Back to the tires, I'm running Kumho Ecsta XS now (180 treadwear) and they might last 2-3 more track days (or through the end of this month) so I need to make a decision pretty soon and get whatever I'm going to use in November on order.

Right now, I am leaning towards buying one more set of street tires and then move to the R-comp's early next year. By then, the spec boxster series should have selected a new spec tire which will probably influence my selection (as I would like to end up in BSX eventually).

I will look into the Hankook RS-3...

I had the XS--actually still do in the basement-- wore like iron and worked with the -1.0 camber I got into the front end. I put on the NT05 to replace them when the XS's started to slide more than I liked and I think I like them a bit better, but they want more camber than the XS and are now down to about 4/32 after 10 track days; the XS still has 6/32 after 12 days. The Nittos seemed to brake and turn better while the XS seemed to have a bit more lateral stick. Both are very forgiving tires except in the wet.

The Hankooks would be my next tire except they don't carry a 275/40/18 size that the Nitto does--trying to keep abs gremlins from acting up when you get too far away from the F/R size differential.

jsceash · 10-05-2011, 12:19 PM

The Hankooks would be my next tire except they don't carry a 275/40/18 size that the Nitto does--trying to keep abs gremlins from acting up when you get too far away from the F/R size differential.

That a hugh tire for a Boxster most manufacturers spec that tire at 26.7" to 27". The rubber that came on mine was 25.1" front and 25.0" rear. I thought I was pushing going on a 265-35ZR-18 that is 25.3"

MikenOH · 10-05-2011, 03:15 PM

The 987 18" rears are 265/40/18 with a OD of about 26.3"; the 275/40 is 26.6".

The std. 987 18" front is 235/40/18 with a OD of 25.4"; the 245/40 runs about 25.6".

So by moving up a 245/275/40/18 combo, you keep the same rough proportions between the two tire sizes. This tire combo size is very popular with the Cayman crew.