Lerxst

iTrader: (2)

Luv'n the autoX and will be needing new street tires next year to replace the potenzas that will maximize my performance, without going to Rs, and keep the front/rear stagger to keep the VDC happy. I've read the threads and visited the manufacturers' sites and am thoroughly confused with the choices. On my stock Track rims (18x8 & 18x8.5), what would you guys recommend? Do I keep the stock size or go wider?

Stock 225/45x245/45 (0.7" stagger)
Toyo T1R, Bridge S03, Mich Pilot Sport, BFG KDW, Yoko ES100

245/40x255/40 (0.3" stagger)
Toyo T1R, Bridge S02 or S03, GoodYr F1,Falken RT-615, Dunlop 9000, Pirelli PZero

245/40x265/40 (0.6" stagger)
BFG KD or KDW, Pirelli Pzero, Mich Pilot Sport, Bridge S01, Conti Contact2, Falken 451 GRB

Any I'm missing?

Thanks guys!

davidv

iTrader: (2)

I’ve posted recommendations from Consumer Reports several times. Please search “best tires.” Why not replace the tires with the same size?

03Z33

iTrader: (49)

If your car has no suspension mods, you will want to run at least a 245 front to make up for lack of camber (too much roll)

The stickiest tires out right now are the Advan (Yoko) Neovas AD07, the Falken RT615, and the BFG KD's (not KDW's!)

245/40/18 all around works great

or you can run a 255/40/18 rear (too tall in my opinion but good for keeping "stagger"

or you can run a 265/35/18 rear

Lerxst

iTrader: (2)

265/35 for the back would open up my options, but according to my calcualtor, they are smaller than the front. 25.3" vs 25.7" for 245/40s which would definitely confuse the VDC.

If I go 255/40 or 265/40, that will change the geometry of the tirewall relative to the wheel. Will that cause any problems for the tirewall during autocross on the 8.5" wheel?

Could I get away with 275s, or is that pushing it on an 8.5" wheel?

Lerxst

iTrader: (2)

No luck in the searches... oh well. I'm thinking wider tires would be stickier, no?

03Z33

iTrader: (49)

You can run 275/35/18's on the 8.5" track rim. I actually ran that size on an 18" touring wheel (AVS Sports). It looks a bit funny, but works OK.

If you run a 275 rear then I would run the same front or a 265/35/18 front.

The shorter tire doesnt' affect VDC that much, it's more the ABS... You turn those off anyhow when you're at track/autocross. On the street it will be fine.

Lerxst

iTrader: (2)

Just found the chart... thanks David.

MannishBoy

iTrader: (1)

I was thinking about KDWs with 245/40x18 fronts and 245/45x18 in the rear. The 245/40s in front are very close to the 225/45s stock, so VDC should be good.

davidv

iTrader: (2)

Great. If your primary concern is autocross, look for a tire with superior “dry” performance. Buy dry performance, and be cautious on the street in the rain.

Lerxst

iTrader: (2)

I THINK I've got it narrowed down to three options.

Toyo T1R 245/40 & 255/40 for approx $1025CDN from Onlinetires.com
- Lots of happy users on the forum.
- A little concerned about the 0.3" stagger.

Falken Azenis RT-615 245/40 & 255/40 for approx $1125CDN from Tire Direct
- Autocross buddies say this is the best street tire for autoX with good durability and decent rain performance.
- Concerned about the 0.3" stagger.

BFG G-Force KD 245/40 & 265/40 for approx $1250CDN from TireRack.com
- An informed acquaintence says these are great tires.
- A great fit for the wheels and maintains a good stagger.

Any thoughts?

MannishBoy

iTrader: (1)

You're luckier on the rears than I am, since you have a wider rear wheel. I can't go with the 265 because of the regular 2003 18s are only 8 inches wide in the back, vs 8.5 on the track wheels.

I actually like the idea of the same width tires all around though, as it will help negate a bit of the push.

jun14scr

iTrader: (1)

psh, you can fit 275's on 8's!

go with the falkens, non-staggered.

FritzMan

Do a search on this forum to read up about some of the postings I've made on Kumho MX and Falken RT-615 (which I'm running now). Try Vulcan Tire for Falken pricing. Also, try to avoid Tirerack or any other vendor which insists on using only UPS as they rape you with duty charges crossing the border.

I'm running four 18x8.5 Track rims so 255/40/18 RT-615 all round works great. Zero VDC issues running non stagger, the same goes for my winter non-stagger Blizzak setup.

IMO, I wouldn't squeeze anything more than a 255 in the back and 245 in the front. Anything larger and you're simply weakening the sidewall which results in decreased steering response & feel. Stiffer R compound sidewalls can tollerate the oversizing a little better.

GrassrootsMotorsports.com did a comparison recently and the Azenis (both generations came first & second, followed by the Yokohama, and then BFG and/or Falken and finally the MX.

The Falkens will overheat so if you Solo2 format is small run groups it wouldn't be a good setup. They need at least 15 minutes to cool off. They offer more lateral grip than the MXs but the longitudinal grip doesn't seem to be as impressive. Also, you can't rotate them which kind of sucks.

Lerxst

iTrader: (2)

Thanks Fritz. When recieving via UPS, I always clear the paperwork myself so I don't pay the outrageous brokerage fees. Here's that tire comparison...

http://www.grassrootsmotorsports.com...5_tiretest.pdf

I'm pretty much sold on the Falken RT-615s with 245/40 & 255/40... $1070CDN from Vulcan Tire. Gonna still look at Toyo's a little more, but have pretty much made up my mind.

The autoX usually consists of:

-50-70 second run
-10-15 minute wait
-Second run
-60 minute wait
-Third run
-10-15 minute wait
-Fourth run

I'm thinking that should give ample cooling time.

Fritz, what tire pressures are you running with?

Thanks to everyone for posting here and in other threads.

FritzMan

The RT-615s require surprisingly low pressure.

I've been running almost street levels of 35-36 psi. Anything higher and the tire feels balloon'ish. Even with only 1.1 deg camber up front, there's no rollover (on 8.5" rims) at 35 psi.

The Kumhos required 43-44 psi.