drivesolo

iTrader: (6)

I'm not sure if anyone that can this answer this questions is avalible to see this until after the 12th of this month, but here goes.

I don't know how many 350Zs will be running in this week's Solo II Nationals at Topeka, KS but I'm willing to bet that most of us are really interested and will be looking at the type of equipment that the Zs there will be running, especially their selections of wheels and tires.

Like a lot of folks on this forum I've been looking long and hard to find the right sized autocross tires and wheels for my Z. My problem is a little bit more complex since I'm also trying to stay in Stock classes. I don't know if anyone is attempting the same thing but I'd appreciate the feedback on what equipment you're running.

So, if you happen to be at the Solo II Nationals and your able to contribute any information pertaining to this thread I'm sure all of us that are interested would greatly appreciate the info.

D'oh

I won't be at nationals, and I'm pretty new to the AutoX scene (only been to six of them), but here's what I will be doing:

I also want to stay in the stock class, so I've just bought some Enkei RPO2-J (18x8x35mm offset) and Kumho V700 @ 265/35-18. I'll be running the same size tire on all four corners.

They arrived last week but came with 9" wide wheels instead of the 8" ones I ordered so I had to send them back.

The correct sizes should arrive Wednesday Sept. 10, and the next AutoX will be Sept 21. Hopefully they'll get the correct sizes this time and I'll get to try them out.

Good luck!

-D'oh!

Vlad

I'm quite interested in answer too.
Since I just started (2 Autocrosses) I'm not the one to teach, I'm the one to listen.

I like autox a lot, and I'll probably go to 3 or 4 more before snow falls. To learn to drive. I'm not going to do anything to the car till winter. During winter I'll do what I can to better the car and stay in stock. That's the plan.

So I sure hope somebody will be able to tell me what tires is the best for autox.

drivesolo

iTrader: (6)

This is my first year seriously attempting autocross. I'm sorry to say that it hasn't been much of an attempt because things keep getting in the way of me making it to as many events as I would like. I'm glad that I have the Z but my biggest issue with it right now are finiding the correct tires that will work best for the maximum allowed wheel sizes.

I've spoke at length to a couple of guysi n my auto club and in the WWSCC series that I've been running in. I've decided to stay with the 18x8 (+33 mm) wheel size that comes with the Performance package. Since the front's 225/45-18 is a very difficult size to find I'll be looking to go with 245/40-18 (less than 1/4" dia diff). I do have a little concern that by going down to a 40 series tire, especially in the front because it will not be forgiving at all. Shorter wall = stiffer wheel/tire setup but, as someone pointed out to me, when the wheel cambers (in or out) during high cornering loads it will effect the contact patch of the tire even more than a higher profile tire. Possibly creating a even worse understeer problem. Also less flex in the wall will mean that the seat-of-the-pants feel for when the car's tires are going to get loose is less detectable and requires quicker reflexes to correct.

I'm hoping someone can give us some feedback on this that has actually tired this setup.

As far as competition rubber.... for the rears there's plenty from 245/45-18 to 265/35-18, but I still haven't been able to find a single R-compound tire out there for the 225/45-18 or the 245/40-18 sizes. With the exception of Hoosiers (245/40-18) that are over $250 each through Tirerack. Ouch!

D'oh

I'm currently running 245/40-18's in front on my street tires, and they seem to have balanced the car a bit better than it was with the stock tires. Not sure if this is due to additional width or due to more experience or due to different compound. I have Yokohama AVS ES100's in front. Anyhow, my point in this was that something about the new tires seemed to help rather than hurt the cornering balance.

When I first got the tires they felt a bit more squirmy than the stock 225's, but I think that was because my stock tires were basically bald at the time. I therefore wouldn't worry too much about the breakaway being too sudden.

Finally, for race tires I don't think you need to worry about the overall tire size since you will be running with TCS/VDC off on the track. As I said, I'll be using 265/35-18 all around, which will be 5.2% too small in back, and 2.6% too small in front. Hmmm, maybe I'll need 3rd gear?


-D'oh!

drivesolo

iTrader: (6)

Thanks for your feedback D'oh. I think I'll go with the 245/40-18's up front. I was thinking Toyo T1-S's all around, but I'm open to recommendations based on experiences. Are you running those 265/35-18's on the stock wheels?

I know that pretty much everyone is running 17's which I'm tempted to do except that I don't think the stock 17 wheel sizes would work well as an option for tires in Stock classes. I could be wrong though. What're your reason's for running 18's? Just curious. Are you running in Stock or Stock - Street Tire class?

I'd like to find competion tires in 245/40-18 but I've had no luck. Anyone out there find any that won't break the bank and that'll last a whole season?

D'oh

I want to stay in the stock class.

I'm running 18x8's because that is the standard size on the Performance model. The SCCA rules imply that if you run 17's on the performance model you would have to go into a modified class. I don't know if the rules are enforced that strictly, but I decided not to take any chances and just run on the exact same size wheels as stock.

I went with the Kumho V700 265's because they were just about the least expensive tires I could find. The Hoosiers were available in a 245, but were more money, and there were some Pirelli P Zero Corsa and Michelin Pilot Sport Cups that were way too expensive. It basically came down to Hoosier in a 245 or Kumho in a 265. I decided to gamble on the Kumho and see if they would fit on the wheel.

I'm off to the tire store to see how they look.

-D'oh!

rktjhn

I have the Track model and run on Hoosiers for the Nationals, they don't work well in water, Kumho does better.
I ran 275 back and 245 front both 35 profile, and the stillen sway bar on the middle setting. The car seems to handle better, I just didn't drive well in an inch of rain we had Thursday, Friday dried off and I ran well, dropped 1.8 seconds on the second run and was having a killer 3rd run, probably around 51, when I miss judged and turned wrong, almost having to stop the car to make the turn, oh well, always next year.
Have been running kumhos, 265 rear and 225 front, the 265 will fit the front, tire rack gives some miss info to sell rims
Alignment is important, I went neutral all around, and for the Nats did some toe out up front.
Someone asked about rim sizes, if your car has 17 you have to run 17, if it has 18 then you have to run that. Cobra Mustang rims will fit the 17 inch cars and are very close to the same offsets, nobody really cares much unless you start to win all the time

zoasis

drivesolo,
I'd go for the Enkei RPO-2j's with the Kumho 265/35's front and rear. There's no reason not to go as big as possible up front with the Z. I ran in BSP at nat's, drove OK the first day and not too well the 2nd day but one things for sure, I'm glad I had 275's up front.