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

thstone · 09-29-2011, 02:20 PM

Ok, I've been going to the track regularly all year and have accumulated 16 track days thus far. I've been driving on low UTQG-rated street tires (~180). I should have about 22 track days by the end of the year and plan for a similar track schedule in 2012.

My car is a 1999 base model with stock suspension. Alignment is maxed out at -1.5 deg camber. Otherwise, all I've done is add safety equipment such as a racing seat, 6-pt harnesses, and a Brey-Krauss roll bar extension.

My goals are to continue to work on my driving skills and become more competitive in my class in time trial events (recently TT licensed). I'm thinking about a RoW030 or PSS9 suspension upgrade early next year (tax return money).

But right now, I'm thinking about making the move to an R-compound tire such as the Toyo R888. I would get second set of wheels for the R-compound tires and swap them prior to each track event.

Is this a sensible move or should I stay with the street compounds?

Topless · 09-29-2011, 09:17 PM

Welcome to the slippery slope Thomas. My general recommendation is to run DEs in your car for 1 year on street tires and re-evaluate. You are here... join the party!

Some considerations:

R-comps crave negative camber so you may want to do PSS9s first to get the most performance and life out of them. Otherwise you will shred the outer edges of your new soft compound tires and tire costs will soar (ask me how I know this

). $$$

You may find that you actually need two sets of wheels/tires with R-comps. 1 fresh set for timed runs and one older set for practice runs. $$$

888s are really nice tires for the first 10 HC but fall off fairly steadily after that. They also run best with -3 deg camber which requires lots of suspension $$ to get there. NT-01s have softer sidewalls and are more camber forgiving on our cars. They also seem to be more consistent throughout tire life. If I manage my tires well I can get 50 HC (10 days) on a set of NT-01s.

Lastly, R-comps are marvelous once you have them dialed in and are totally predictable during all day lapping. They have often been compared to crack cocaine in terms of addictive properties except that R-comps are a lot more expensive. $$$

So if none of this frightens you, put $2k in the bank for your 2012 tire budget and start shredding some soft rubber.

If you come out to the PCA Pomona Fairplex TT in Nov, look for me & I'll take you out for a session. My car is a fully developed BSX Boxster on PSS9s, comp sways and NT-01s at min. class weight.

j.fro · 09-30-2011, 02:58 AM

At our last autocross, the DE/AX chair wanted to show us just what the difference between R-comps and street tires is. He did 3 runs on street tires, then swapped wheels and did 3 on R-comps. The car is a modified 914 with a late 911 SC 3.2. On the street tires he was high 50's...the r-comps consistently dropped 3-4 seconds from his times.

Using R-comps, I can get about 16-18 AX's from the rears (a bit over 1 season), and 25 or so from the fronts (end of the second season is pushing it!) I drive to and from events on these tires, which is 120-150 miles round trip.

Just did the math...looks like I'm paying about $50/event for tires! That's just under $10/run. Nothin cheap about racing Porsches!

BYprodriver · 09-30-2011, 10:06 AM

Michelin Super Sports

MikenOH · 09-30-2011, 06:10 PM

A couple of thoughts:

As a former '99' MY owner I'd suggest the ROW 030 suspension--very cost effective.

Regarding tires and assuming you're on stock 7"/8.5" 17" rims, think about these as alternatives to R comps if you aren't trailing your car:

Nitto NT05
Kumho XS
Hankook RS-3

All can be driven on the street, have way better traction than regular street tires, good for minimum 10-12 track days depending on how bad you beat them up--and best--not real expensive; I think the Hankooks are under $500 for the set--dirt cheap.

A second set of wheels is the way to go, BTW; used boxster style wheels are pretty cheap ($500?).

Last I didn't hear anything about brakes; if you're doing DE's think about a pad for tracking; Pagid makes a few that will work if you use OEM pads on the street.
Same thing about fluid; I like Motul 600

Mrmaddbrad · 09-30-2011, 06:14 PM

Bottom line:

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)...

Now if youre just looking for fun to money ratio, performance street tires will get you what you need with a ton of fun behind them... But R-compounds will always be faster (unless theres standing water on the track), so you just need to decide if its worth the money to you.

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.

jsceash · 10-05-2011, 07:45 PM

Wow! sorry I didn't know the tires between a 986 and 987 were sized so differently. Mine had the sport Boxster SII wheel option from new and came with PS2, 205-50ZR-17 and 255-40ZR-17.

thstone · 10-05-2011, 10:04 PM

Sorry, I should have mentioned that my wheels are also the 17" and I've been running 225/45/17 front and 255/40/17 rear which seems to be what most of the Spec Boxster guys run.

jsceash · 10-11-2011, 07:32 PM

The Hankook tires were an improvement. In a 28 Min sesssion they gained about 10 #. The Times Through the session did not fall off. With the exception of the first lap every lap was in the 2 min 39 sec range on the last session of day 1 Best time I ran. The second day we worked on brake points all 4 sessions. The PS2 started to fall off after 5 laps.

Pat · 10-11-2011, 07:56 PM

I'm surprised no one has mentioned oil starvation yet in this thread. Especially considering the "slippery slope" comment.

thstone · 10-12-2011, 01:05 PM

@ jsceash - thanks for the feedback on the Hankook's! Sounds like I will try them next. My current set of Kumho XS's will be done after next weekend's pair of DE's.

@Pat - Hmm. I've heard oil starvation mentioned in passing but nothing in detail. I'll start a new thread in Boxster racing to see what everyone has to say. Thanks for mentioning this - sounds important!