[s-cars] HPDE Track Tires

[LL - NY]

On something as heavy as Miss Piggy, it won't take too much to warm up
R-comps, especially with AWD to help warm up the rears. R-comps get a bit
dicey when cool (say around the mid-forties) but with a reasonable warm up,
they should be fine, just be aware on your cool downs that they could bite
you if you over do it. They will actually last a bit longer as the others
said, due to their single purpose nature.

As for camber, yeah, you may not be able to dial in camber to the exact
desired figures by just sliding around on the 2B plates, but if you mark
your street settings (to get pretty damned close) and simply max out your
track camber, you'll be using things to your best advantage. Be aware that
the stickier compound of the R-comps (when warmed up) will also get the car
to roll more, so get as much negative camber as possible for your track
running. If you can afford it, adding some roll stiffness will also help,
although the quicker transition rate (if you add a LOT of roll stiffness)
can catch you out if you approach things a bit too casually.

R-comps have really progressed a great deal since the days of the V700,
however. You may well be able to find some pretty decent prices on some of
the lesser known R-comps, such as the Hankook Z214 (go for the C30 compound
on Miss P, its a bit harder and more likely to not overheat under the weight
of the pig), and the Nitto NT01, and there are some harder compound more
dual purpose tires from Yokohama also available. With some searching (pick
up a copy of Grassroots Motorsports) in the classifieds, you may well be
able to have your cake and eat it too in this case.

HTH,

LL - NY

On Thu, May 13, 2010 at 9:40 AM, Manuel Sanchez <manuelsanchez at starpower.net
> wrote:

> Fellow S-heads,
>
> I am looking into purchasing a set of tire that will mainly be used
> for HPDE events. I typically go when it is relatively cool outside.
> This is typically 4 track days per year (April and November). Often
> the mornings are cold, 40-50 degrees F (4-10C) , warming up to low
> 70s F (22C).
>
> I have currently been running Toyo T1Rs and I didn't really like them
> too much. I am probably over driving them. They howl alot and the
> sidewalls really roll over (in my opinion). I sometimes run stock
> camber, but other times run -1.5 degrees of camber (I actually don't
> know what the limits are of my 2B Camber plates are). I am running
> 2B's coilover kit with 600lb rear springs and I think 440s in the
> front. Koni Yellows, adjustable in the front.
>
> So while I'd like to ratchet up my performance a bit at the track, I
> don't have a Donald trump bank account, so price will be a
> consideration.
>
> When I took my Toyo T1R's to my reputable tire dealer, he said these
> tires weren't really designed for what I've been doing to them, and
> recommended Toyo RA-1's (instead of the R-888) when I am ready, as
> the RA1's have proven to take a beating (I have an Avant).
>
> My wheel size is 17" x 8".
>
> I am looking likely at 245/40-17 (I currently have 235/45-17's).
>
> Most of these DOT R compound tires seem to hover in the $250/tire range.
>
> Tire rack has a special for Michelin Pilot Sport PS2's for $167/tire.
> That's essential a buy 3 get 1 free deal compared to regular price.
>
> The delta between a DOT R compound and these is about $332.
>
> I have read in GRM that to really get the most out of a track tire,
> you need to run lots of negative camber. Toyo lists -2.5 to -5
> degrees camber on their website. I have run -1.5 degrees of camber
> (don't know if I can set my plates up to get more or not). I also
> drive my car to the track and that's usually a 500 mile round trip
> each time, so I have thought  that more aggressive alignment might
> chew up the tires I use to drive down a bit (the beauty of the avant
> as a track whore is that a complete set of track tires fits
> comfortably where the 3rd row seating is located).
>
> The Michelin PS2's have a wear rating of 220.
> Toyo RA1's have a wear rating of 100.
> The Michelins are about 3-4 lbs lighter / tire than the Toyo's.
>
> So:
>
> Has anyone run either of these tires on their urS at the track?
> If so, what did you think of them?
> Based on my experience with the T1R's I would like to find a tire
> with a sidewall stiff enough that it won't roll over (I have had
> other tires that did not seem to roll over onto the sidewall as
> easily as the Toyo's, Goodyear F1 GSD3's and some Dunlops that I
> can't remember).
> Would an R Compound tire be a waste, since I have not run at least
> -2.5 degrees of camber?
> Would R Compound tires be a waste because the track temperatures when
> I attend HPDE's is cool (in my opinion), or are those ambient
> temperatures warm enough to get an R compound tire to really shine?
>
> I could also let this PS2 sale slide by and when the time comes buy a
> cheaper set of Hankooks or Kuhmo street tires to beat on at the
> track. They seem to be substantially cheaper.
>
> Thanks.
>
> Manny
> 95.5 urS6 Avant (mostly RS2'd)
>
>
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