C6_Racer_X

Not a Corvette, but at least it's a Chevy.

The vehicle is an S10 pickup truck (mostly 1997). Hey, at least it's a two seater, no?

I'll be running in STX, so tire choice is limited to 200 treadwear rating or higher.

I'm trying to stay with the appearance of a "nasty old work truck." I have stock 15" wheels available (currently 7" rims, but could be widened to 8" or even 9" rims), and I have a beat up set of the 16x8 alloys (ZQ8 RPO code wheels). Either will work. I'm trying to avoid "shiny new super-duper wheels" to stick with the "nasty old work truck" appearance.

The sticky 200 treadwear autocross specials (BFG Rivals, Bridgestone RE-71Rs, Kumho V720s and others) seem to be quite limited in selection for 15" and 16" wheels. It looks like 225/50R16 or maybe 225/45R15 or 225/50R15 are the widest available in those sizes. All choices seem to be 7.5" wide at the tread +/- 0.3". I have room for 255 section width tires, like 255/60R15's (late c3 corvette sizes) or 255/50R16. There's nothing in 200 treadwear in those sizes.

There is one other choice that looks a little interesting, but I'm not sure whether the added tread width will make up for the harder, less grippy compound. BFG makes a Sport Comp 2 in 255/50R16 with a 320 treadwear rating. I'm not sure how much grip is lost to the harder, longer life tread compound, but the tread width is 10", about 2.5" wider than any of the 200 treadwear autocross specials. In my mind, 1/3rd more tread width has to be worth something, even if the compound is not quite as grippy. Does anyone have any experience with those tires compared to the usual 200 treadwear "autocross specials"?

The other choice is to find some 17x9 "nasty old work truck wheels" (not sure where those would come from, but high mileage ones from a junkyard would be preferred), and fit RE71-Rs or Rivals in 255/40R17 sizes. The two down sides I see with that are cost (my budget isn't unlimited) and the difficulty to maintain my "nasty old work truck" appearance.

CorvetteForum always has opinions on things like this. Some of them are even knowledgeable and helpful.

I'm looking for any input on this choice. Actual experiences would be most helpful, even if it's with C3 or C4 Corvettes or other vehicles.

wtb-z

If you are solving for speed, the widest Rival S or RE71R you can get. The RS4 needs too much heat to be useful at autocrossing, and a tire like the Comp 2 will be much slower.

For what it's worth, if I was starting with a car with weird dynamics, not really solved dynamics, (e.g., an old compact pickup) I would probably start with the RE71R over the Rival S.

Tomswheels

C6_Racer_X

I really want to stay out of 17" wheels if I can. First, there's the irrational desire to keep the look of a "nasty old work truck." That's not absolutely necessary, but it's a big desire of mine, whether it's rational or not. Actually, I'm playing to a competitor's irrational feeling that trucks aren't "sports cars" and shouldn't be autocrossing. His "sports car" is an Acura Integra. He doesn't want to get beaten by a truck, especially a nasty looking old work truck, so I'm trying to keep the appearance to be as far from "sports car" as possible.

There's also a budget issue. I'm probably going to be in serious trouble if I spend more than $200 in dog money ($1400 ish total) on wheels and tires for this project. That gets really tight when I have to include 17" wheels in the budget.

OK. The widest available 15" tires are 245/50R15 and I can get either Rival S 1.5s or the Hankook Ventus R-S4 in that size. There is no choice for the RE-71R that wide for a 15" tire.

I know 15x9 will fit on the rear with the 245/50R15 tires. That's much smaller than what some folks have successfully run on these trucks. 15x10 with up to a 305 tire can work without clearance issues on the rear. In the class I'm in for SCCA Solo (STX), I'm limited to 9" wheels, though.

The "wisdom of the Internet" seems to say that 15x8 with 245/60R15 tires is the widest I can go at the front without clearance issues, but with the 245/40R15 tires, I'm also over 4 inches smaller on the diameter, so I'm not certain that "clearance issues" reported by others are applicable to this tire size. I do see reports of folks running 16x8 wheels with 255/50R16 tires on the front (all four corners actually) without issues, so I may try the 245/40R15s on the 15x9 wheels.

For now, I think I'll get a pair of my S10 steelies (currently 15x7) widened to 9" rims and get a pair of the 245/40R15 tires mounted on them. I know those will work at the rear. I can take the front springs out and check clearances at all angles of suspension bump and droop and across the full steering range and see if I have clearance under all conditions with those tires. If clearance is good, do the same for the other pair of wheels and get matching tires. If I don't have enough clearance at the front, I can go to 225/45R15 tires of the same model on 15x8 (widened) wheels at the front and run a slightly staggered setup that way.

The question is, do I jump right to the Rivals on a setup that I'm not 100% sorted out on, or do I run a set of Hankook Ventus R-S4's to get things in the ball park for part of a season, and upgrade to the BFG Rivals when I've got everything sorted out. I wish I could run the RE-71Rs, because I'm really familiar with those, and they would probably be best for sorting things out, then go to the Rivals.

Having the R-S4's might be good if I want to do a track day or time trials with the truck, too. I think those would work better on a road course track than the Rivals.

Tomswheels

C6_Racer_X

That's not it at all, sir.

After reading your post, I did put a few hours of additional time into researching the 17" wheel choices. I also liked that the RE-71R tires are available for the 17" wheels.

My biggest problem was that any 17x9 wheels that fit (including -12mm offset required, or 4.5" back spacing) were $180-$300 per wheel. After looking at the budget, I just can't quite get to that level at this point. It also didn't help that the designs were all "brodozer" wheels and not in keeping with the "nasty old work truck" look I'm going for. Like most racers and autocrossers, I could probably live with ugly if it was really faster. The budget issue is something I'd have more difficulty getting past.

If I could find a 17x9 wheel that fits properly (proper lug pattern and back spacing/offset) and was under $500 for a set of 4 wheels, I might consider that route. Right now, I'm not seeing a 17" wheel solution that fits within my budget.