PCA SDR

I need advice regarding tire purchase for my Boxster S. This is Vic Aramati, I live in Vegas and try to make as many of the SD AXs as I can.

I purchased this week a '01 Boxster S to replace my '00 Boxster. The S came with 18" wheels, front Dunlop Sport 2000, rear Dunlop Racer. The tires seem to have about 5K miles left, however I do have a steering wheel vibration over 80 mph even after balance by the Tucson Porsche dealer. Their recommendation was to replace the existing tires with a matched set with a Porsche N rating.

The question is what do I replace these tires with? I need a good all around performer for street and AX. By the way what is the Porsche N rating?

I would really appreciate if you advised me on the top 3 tires I could purchase. Thanks.

This is what I have on the car right now:
Front: Dunlop SP Sport 9090 N-0 225/40 ZR 18
Rear: Dunlop SP Sport Super Sport Racer 265/35 ZR 18
Sorry for the previous error.

You have the Dunlop Super Sport Race (DSSR) tire on the rear? If this is the tire I know you have an R compound rear tire with a harder compound up front. I cannot find a 9090 tire but see a 9000 tire which has a treadwear rating of 280. If the rear is a DSSR, then that is rated at 60. Not a good combination if indeed that is what you have.

In deciding upon what new tires to put it is entirely depends upon what you plan to use the car for. Street, Street/Auto-x, Street/DE/TT, etc. It also depends upon which class you want to compete in if you are off the street. More information about what you plan to do would help with recommendations.

Thanks for the reply Kary. The types I quoted the second time are correct.

The front Dunlop SP Sport 9090 N0 is an OEM tire, is listed in TireRack, wear of 280 and quite expensive.

The rear is a Dunlop SP Sport Super Sport Racer, well priced on special at TireRack and lists a wear of 60. (Does this mean that the rear tires wear a lot slower than the front?)

I would like a tire that will do well on combo of Street/AX. I am also assuming now an AX class of MSS.

Does that help?

aramati wrote:Thanks for the reply Kary. The types I quoted the second time are correct.

The front Dunlop SP Sport 9090 N0 is an OEM tire, is listed in TireRack, wear of 280 and quite expensive.

The rear is a Dunlop SP Sport Super Sport Racer, well priced on special at TireRack and lists a wear of 60. (Does this mean that the rear tires wear a lot slower than the front?)

I would like a tire that will do well on combo of Street/AX. I am also assuming now an AX class of MSS.

Does that help?

Vic, the higher the treadwear rating the longer the tire lasts. The DSSR at a rating of 60 will wear much more quickly. Also you cannot use that tire in MSS (street Stock). You must have a tire with a rating of more than 100, 140 or 200 I cannot remember off the top of my head. So in your current configuration you would have to run in MS and would be at a severe disadvantage without a matching soft compound tire in the front of your car, particularly in auto-x where turning in everything.

I have not picked a Street Stock (non R compound) tire for a long time so others here on the board might give you a better recommendation. The last time I ran Street Stock I ran Pirelli's and Bridgestone S02's. Many years ago.

That's a very good point Kary about the impact the tires mismatch on the classification.

I will buy a new set as soon as I get feedback on a good street/auto-x; definitely before the March AX.

There are several other tire threads on the Forum that you can search on, but to save time, to run in MSS you need to run tires wit a tradwear>100.
Falken Azenis is a popular tire, but does not come in 18 inch, other popular SS tires are the Kumho Ecsta MX, BFG TA KD and Yokohama ES100.
The N rating is a Porsche specification for tires. Nice thing to have, but not a big issue.

Greg

Greg Phillips wrote:... to run in MSS you need to run tires wit a tradwear>100.

Greg- the new rules say anything less than 140 treadwear is excluded from Street Stock class. Anything 200 UTQG or under also is given point penalties.

The Kumho MX would be a good choice for street/autox on the 18" wheels on this car. It's a good, high performance tire with a UTQG of 220 (no points) and has good pricing at the Tire Rack: http://www.tirerack.com/tires/Sizes.jsp?make=Kumho&model=ECSTA+MX 225/40-18 = $108/ea. and 265/35-18 is $178/ea on special right now, as opposed to the BFG TA/KD, at $194 and $257.

TT

I am very happy with the BFG TA/KDs - they have a treadwear rating of 200, so they are 0 points, yet they feel very sticky (at least for the first 6-7000 miles - depending on the number of events you do).

I drive a "showroom stock" Boxster (2.7L) and consistently have times competitive with the Boxster S's in MSS and the 996's in NSS, and I think the good grip and handling of the tires have something to do with it.

My last set was about $950-$975 installed, balanced, taxes, etc., at Discount Tire (17" tires), but you need to order them a few weeks in advance, as they are usually in short supply.

Note that they are not great in the wet - they are definitely "dry" tires. Also, although you can get maybe 9-10000 miles out of a set on the street, after around 6500-7000 miles they will harden up and start getting slippery on the track.

If you can run BFG T/A KDs and still stay in M/SS that is the way to go, IMHO. They provide great grip and in the 18" size are very responsive with quick turn in. These tires were on my car when I got two top tens on the way to winning M/SS in 2001 with my '00 Boxster S.
My only gripe in that the fronts really want a slightly wider tire than a 225. The car tended to understeer. Perhaps they make a 235 or 245 now? Keep the 265 width in the back.

Kim Crosser wrote:I am very happy with the BFG TA/KDs - they have a treadwear rating of 200, so they are 0 points.

Actually, Kim, a 200 treadwear tire is 1 point, the way the Zone 8 rules are currently written. If they weren't, I would still be running GS/S with my Falken Azenis, which are also 200 treadwear. Because I have oversize sway bars on my car (for 2 points), that single point for the tires puts me into GS.

TT

I have an '02 Boxster S. I recently replaced the stock Michelin Pilot Sports with Michelin Pilot Sport PS2, front and rear. And am I am very pleased for the following reasons:

- It was like having a new car. These tires are sticky and loads of fun, both on the street and at the autocross track.

- The previous set (the Porsche Pilot Sports - Michelin makes special ones for Porsche) had pretty good tread life for a performance tire.

Paul

I put the Yoko ES100's on my Boxster S and was very pleased. Far better ride AND handling than the P-zero's for a fraction of the cost. I think they make a very nice all around tire. You may lose a 10nth or 2 at the AX, but the wear, rain grip and ride are much better. They are all compromises, so you need to tell people your priorities in the tire as no tires does everything best.

I have the 2001 Boxste r S with 18" wheels. If I go on the front with a 235 instead of the standard 225, as suggested by Chris,would I need a different wheel?

no problem, rims can handle some variation in tire size.