V710 vs non-DOT race rubber

[BobDixon]

Just curious if anyone has experience/opinion on whether a 'real' race tire would be stickier than a V710. I believe the Prepared and Modified classes can run race rubber.

Thanks,
Bob
86SM2 or maybe 86XP

[lundgren]

Goodyear slicks or Hoosier Slicks for example tend to be sticker yes than DOT race tires, including the V710

[Clay Turner]

I spoke with Rick Walford on Sunday about tires for his CP Camaro and learned that he can't get either A-compound Kumho V710s or Hoosier 06s in a large enough size. He runs R-compound tires, but the deciding factor is how fast they heat up: R-compound slicks, designed for road race lapping, may or may not be stickier than A-compound when hot, but if they take a lap (or two or three) to heat up, they won't be as effective on a 60-second course.

[BobDixon]

That's a good point. I hadn't thought about how long it would take to heat them up. I'll have to talk to some of the R compound guys at the next event. I have Kumho's right now that I bought used and was just trying to think ahead for when they finally wear out.

Thanks,
Bob

[geoffbp58]

Well, here's my two cents (adjusted for inflation).... I run slicks on the Corvette, R-compound autocross tires on everything else I get to drive (Caryn's BMW, ES Miata, occasionally even the Hotruck). Slicks are grippier, and seem to me to heat at the same rate as DOT tires. They also feel more precise, particularly in turn in. You won't find ANY competetitive Prepared car running DOT tires. I don't personally recommend Hoosier R45's, although they seem to work well in smaller sizes. The next thing to consider is cost- unless I get a set free from Bob Ely (thanks Bob!), I normally buy my tires through the guy who advertizes used racing tires in the back of Sportscar; a set of gigantic tires in nearly new condition (cycled once or twice and at nearly full depth; GT1 guys have a lot of money!) costs about $360 shipped; a bunch cheaper than DOT tires new. I heat cycle them away before I wear them out. One set of tires easily lasts a season, but I'll buy a new set if I'm going to Nationals. Sorry for the long-winded response; it actually wound up being four cents! Have fun!

[BobDixon]

Hey thanks, thats the kind of info I was needing. I was planning on buying used race rubber if I went that way. Do you have a compound and brand preference in case I have a choice.

I think I'll go ahead and run the Tiger in XP since I don't feel like putting interior pieces back in just to run SM2. I would run in BP but I think the car may be too light. I'll have to get it weighed.

Thanks,
Bob

[geoffbp58]

Hello again! I'm loving life on Hoosier R35's these days; Rick Walford is using them also. I'm not sure what Bob Ely is using on his Mustang; I think he's been doing a bunch of testing lately, and he's used Goodyears extensively. I think you should run BP anyway; more people to talk to on grid! I have a set of scales if you want to weigh your car; e-mail me and we can make arrangements. I don't think you're gonna get protested for weight anyway; although it might be an issue at the National Tour event and for sure if you're going to Nationals. It's pretty much the same ol' people in BP; myself and Tom Exley in his RX7, (hopefully Ken Ennis will be back with his Corvette, too), and unless you're running the ultra-light helium-filled Tiger, I think we'd all welcome the competition. Have fun!

[BobDixon]

Tigers were never light anyway. I am pretty sure she'll come in at around 2500lbs or more. Nothin but steel on that car. I doubt anyone would protest anyway since I'll always be dead last. :p My used Kumho's will probably last me all season but we'll see.
-Bob

[Jake Latham]

Bob -

To clarify, Hoosier's naming conventions between DOT and non-DOT race tires is different. On our side of the fence we have:

R25 - Yummy! Barry and Jeff and I run these in the ~1,100# Mod cars
R35 - next up
R45 - next after that
and so on.

There is an R15 compound, and an R60 too, I believe, but neither of those works for solo'ing, I don't believe.

On the Dot side of things, Hoosier has the "R" tire for road racing, and "A" tires for autocrossing.

The fellow that Geoff mentioned - John Berget - commonly has takeoff Hoosier tires for great prices, I recommend him highly.

-Jake

[geoffbp58]

The R45's in the larger sizes are of a different construction- when Matt and I had our shop, we were Hoosier dealers, and Bruce Foss told us the new 45's were going to be the greatest thing ever- soft as a 35, with much better wear. I've been using them for the last few years. The BP/CP popular sizes are 25x13-16 front; 27x14-16 rear. The 27's in particular have a lot of sidewall flex, and have a very peculiar mushy kind of oversteery feel unless run at very high pressures (I wound up at about 28psi). A lot of people started using the 25x12-16's because they were stiffer. I think that's what Tom Exley is using on his RX7 currently, and they work great. I'm a holdout so I stuck with the 27's. (My car would look really goofy with 25's out back, and I just can't have that!) Mr. Ely donated a set of R35's late last year, and I'm actually going decently quick again; the car feels a lot more planted... even though I don't always drive it that way! (At least until the third run at the last event, when the back half of my car almost fell off; very ugly!) I'm not sure if this added anything useful to the discussion, but I'll throw it in there anyway. And thanks for reminding me of Mr. Berget's name- I was searching what was left of my memory and finally gave up!

[Chris_Swearingen]

What size are those kumhos that you really want to trade up to real race tires?

And what is the bolt pattern on a tiger? I am thinking test fit here. 4x100?

[BobDixon]

The tires are 265/45 - 16. I really wish the bolt pattern was the same as a Miata. It's 4x108. I have them on 16x10 wheels. Yeah, they stick way out.:D Makes the car look really mean.