2004S2000

I have new eagle f1 tires 215/45/17 on the front and 225/40/17 on the back. These are on those Shuk wheels so the rears are 9 wide. There is slightly more contact patch on the front and less for the rears despite 225 width, though not enough that I expected a big difference in handling. Now I have them on the car, there is a bit more oversteer, but not bad. Except lane change manuever feels unstable! Puts a wave in the car like the rear might come around. Who in Birmingham can ride with me, feel what the car is doing, and address the alignment accordingly? Anyone else have these tires or similar tire sizes? What did you do RE alignment?

Thanks,

Ken

ROLLINS

Ken, Are you in birmingham, or madison? If you're in madison, then I am close by in decatur. I am wondering what would cause the unstable feeling that you're getting?? Go, make sure that you have the front tires on the front. At WTD last year a guy got new tires before the trip. After having trouble with handling someone notice that the tire shop mounted the fronts on one side and the rears on the other!

jaclarke

I am speaking from the perspective of an '01 with 16" rims, but:

I was warned early that the OE 225 rears have a contact patch closer to that of a 245. Combine that with the natural tendency for these cars to oversteer and what you have done is exaggerate that tendency. When rear traction is marginal to start with, any small change is going to be noticeable.

Short of getting wider rear tires(which might be cheaper), you might consider a larger front sway bar. I have a Sano front bar and stock rear bar on my car and I run Kumho's on the street with 225 rears. I have found that even with less contact patch on the rear, I have only slight oversteer on the street. For autocross, I run 245 rears and 225 fronts and the car is much more neutral than it was without the bar.

ROLLINS

I thought the AP2's had a tendency to understeer. Brought about by changes to the suspension???


I understand what you are saying about the contact patch, and I was gonna bring it up, but I wasn't 100% sure if I knew what I was talking about

2004S2000

I got these wheels/tires from Jim at Tirerack. We discussed the contact patch reduction at the rears, but he felt that the reduction was very minor and would not impact on handling. I think alignment may fix it, but I am looking for a good shop that can improvise and also any suggested settings from people who have gone with tires other than the OEM on a MY04 or later car. My last alignment guy was great, but he's in Wisconsin. I live in Birmingham, by the way.

I don't understand how a front sway bar will fix things. Not doubting anyone, I just don't understand. The front wheels feel almost as responsive as with the OEM tires. I have -1 degree front camber which helped to eliminate the understeer from the factory settings.

I do like the new tires in general. They protect the wheels with a lip, are a quieter ride without the OEM bump steer, and stick quite well. The oversteer I feel on corners is quite mild and easy to modulate. Its changing lanes rapidly that scares me. It's like the front of the car has made the move and settled, but the rear is lagging behind and not done when the front is. Then the rear wants to continue. It doesn't make me slide, but it makes me fear wet conditions.

jaclarke

I was able to find a chart that might help:
http://www.wtrscca.org/tech.htm

Increasing the front sway bar (or decreasing the rear) increases understeer/decreases oversteer. I don't pretend to be an expert, and I knew Honda softened the swaybars with the '02 model to help the situation, but read that it was not enough. The rash of bent S2K's lately speaks volumes to that.

ROLLINS

Thanks for the link, John. Maybe I can learn a little something from this. I don't know if you've kept up in the other threads, but I bought some tires and wheels from Grant. He bought them from Chris (slows2k) Anyway, Chris had 245 tires on the back instead of 225's. I guess the different contact patch between s02's and re750's had something to do with that.

when is the next autocross?

jaclarke

Next autocross is this Sunday, at Milton Frank Stadium. MF is by far our biggest and best site, and with B'ham loosing their site, the best in Alabama.
Course Map

TAC/TVR schedule

Don't forget the School in 2 weeks.
School Flyer

VoIPA

Cool. I'll probably try and make the class.

Slows2k

[QUOTE=ROLLINS,Mar 9 2006, 04:47 PM] Thanks for the link, John.