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View Full Version : Autocross and daily tires in a 15 or 16"?



Boxjohn
10-06-2015, 09:43 AM
I'm looking at setting up a wheel and tire package that does the following:
1. looks plausibly stock, fitting on widened stock wheels. In my case that means 15 or 16" tires
2. Will survive 10-20 autocross days per summer, and not completely roast themselves
3. Comes in a 235-255 front and ideally something wider in the rear
4. is 25.7 to 27.2 inches (roughly) in diameter
5. won't kill me in the rain or burn up instantly when daily driving it
6. ideally is a 200 treadwear or better


So far the best I've come up with is these:

255/50/16 BFG Sport Comp 2's.

I have Comp 2's in my modern japanese other car, and love them. But they don't come in a wide tire for the rear (I can fit at least a 295), I'd be willing to go quite a bit softer compound/lower treadwear, and I honestly don't know how long they'd last autocrossing. My car, as is, plows badly and the 15" Mickey Thompson Sportsmans (think Radial T/A but designed in this century) are absolutely getting roasted on the shoulders even with 44PSI cold.

http://www.tirerack.com/tires/tires.jsp?tireMake=BFGoodrich&tireModel=g-Force+Sport+COMP-2&partnum=55WR6GFSPC2&vehicleSearch=false&fromCompare1=yes



Any thoughts? Also just throwing it out there, is there a non-autocross specific 15" race tire that'd work on an autocross course? Circle track tires are cheap enough that I could just run track-only wheels and tires if I could use the 15" circle track stuff or something like it.

Boxjohn
10-13-2015, 09:44 AM
Any feedback? I'm willing to get very outside the box here, and if the answer is there's nothing that won't just fold over and be roasted after a few runs then that's good info too

j-rho
10-13-2015, 11:31 AM
The roasted on the shoulders thing is likely insufficient negative camber in front, which will continue to be a problem regardless of tire.

For my 15" mags I went with the Avon CR6ZZ. The good news is they're lightweight, last long, perform well with modern compound/construction (roughly equivalent to a Toyo RA-1) but still have the tall sidewalls and tread design for the vintage look. A lot of guys with vintage/replica Cobras and GT40s run them.

The downside is they're under 200TW (80 I think?), they're a little tall, and they're expen$$ive.

Can be found at Roger Kraus racing. Good luck!

Boxjohn
10-13-2015, 05:20 PM
The roasted on the shoulders thing is likely insufficient negative camber in front, which will continue to be a problem regardless of tire.

For my 15" mags I went with the Avon CR6ZZ. The good news is they're lightweight, last long, perform well with modern compound/construction (roughly equivalent to a Toyo RA-1) but still have the tall sidewalls and tread design for the vintage look. A lot of guys with vintage/replica Cobras and GT40s run them.

The downside is they're under 200TW (80 I think?), they're a little tall, and they're expen$$ive.

Can be found at Roger Kraus racing. Good luck!
I got all excited and then saw the price.
400ish a tire.

Figures that almost exactly what I was looking for costs enough to build a decent stroker motor for a set. Good to know for the long term though

CliffsBlueCamaro
10-14-2015, 03:21 AM
I run the 255/50/16 and 225/55/16 BFG Sport Comp 2's on my first gen Camaro. I've done two track days on them, and they did pretty well. The front shoulders did "roast" a little, but just like j-rho said - It is definitely because I don't have enough front camber.

To be completely honest, I think they would work perfect for what you are looking for. I also considered availability in the future when I bought them, but given they are from BFG and the 255's are the OEM size for a C4 Corvette, I think they should be producing them for a while. They are selling enough of them that they seem to be on backorder quite a bit.

rchaskin
10-14-2015, 04:14 AM
I tried the same thing as well, using 15" wheels tires....
I thought my car did really good with them, until I went to 18" wheels.

You may as well just go to an 18, and get a rival or falcon tire. The grip is astonishing.
You will throw rocks at 15's once you make the switch.

The 18's don't ride bad either and they wear pretty good in my opinion.

Just my $0.02

Boxjohn
10-14-2015, 12:55 PM
I didn't realize they were c4 size. Makes sense.

Geometry and alignment improvements are definitely in my future.

I want to stay factory looking, and am on a seriously tight budget. One or the other could have been ignored. If there was a factory look 18 I'd be all over it, and if larger diameters weren't more than the smaller stuff I'd let it ruin the sleeper effect. But both combine to be enough that I'm OK leaving significant performance on the table for now.