burglar

Hi, new owner here as of yesterday, love the car so far.

I'm a 12 year local-level autocrosser - spent some seasons with some great cars, a Type R, a 944, several 350z s, and this year in a 370z.

My local club runs street tire classes, and just dumps a .98 index on top of the standard index. I hate changing tires, so that's where I'm going to be.

I can find a good baseline BS setup here and on SCCA forums, but what would you experts recommend I change for the lower grip tires? Less camber?

Also, any suggestions on tire size?

chiketkd

iTrader: (5)

Why not run STX? The RX-8 seems to be plenty competitive there and you could run some nice power mods on the car?

Isley did an article for SportsCar some time ago on how much faster r-comps were than a top 140 treadwear 'ST' tire and used his BS RX-8 as the test bed. To make the RX-8 work well on street tires within the confines of stock class mods, he still used:

1) koni shocks
2) front swaybar (used the Hotchkis MX-5 bar)

IIRC, in the article Isley used some 245 sized street tires (RE-01r's maybe???) and ran them against his 245 Kumho V710's. I wouldn't run a street tire bigger than a 245 on our 8' wide wheels.

Also, the main set-up difference between the r-comps and street tires was that Isley needed to run the front swaybar stiffer when on street tires to keep the inside rear tire from spinning at corner exit.

Personally, if I added konis and a front swaybar to an RX-8, I'd pick-up a 2nd set of stock wheels and some lightly used r-comps and run a true BS set-up...or just run STX if you absolutely hate changing tires.

burglar

Is there a link to that article? I don't archive my Sports Car mags, and I'm failing at Google to find it. Sounds like exactly what I need.

I'd like to keep the car stock, the mod bug is the slipperiest of slopes for me. That's why I bought the Mazda in the first place - good enough stock, and tough to mod.

Thank you very much for the pointers.

ACR-Mark

I too run my RX-8 in BS trim in an indexed Street Tire class. It's an 09, and except for a very mild alignment, completely stock. I bought a set of Rota P-1's in OEM size, and slapped on some 245/40 Azenis RT-615's. The car is very predictable, but you have to run low pressure in the back in order to keep it from coming loose. I use between 38 and 40 up front, and depending on course, 29 to 32 in the back. The RT-615's are really cheap, but have fallen way behind all the other max performance tires. Next year I will try the Dunlop Star Specs in 245/40. The car will surely have tons more grip, and still be driveable in the rain, for a small cost increase of about $25 more per tire.

burglar

The street tire article in the Sports Car magazine that showed up in the mail yesterday was practically tailor made for me. Star Specs it is.

tmak26b

It's also one of the cheapest tire too, I have them. They are very good tire, but nowhere close to R comps

kjchristopher

iTrader: (1)

When I ran mine in street tire class, I used Koni shocks on all four corners and the Hotchkis MX-5 bar up front, full stiff. Where are you located? I'm thinking of ditching the bar as it isn't really necessary with the r comps.

VS8

iTrader: (4)

dunlop d sport direzza z1 star specs FTW

burglar

I'm in Detroit.

Is the big front bar intended to increase transitional response, or to help keep the inside rear down?

TorqueyPig

Id say the Direzzas