333pg333

Thought I'd try the Racing forum, but not too much help there so here it is:

Our racing is predominately super sprints which comprise of all out 4-6 lap blitzes. We mostly use R-spec rubber down under of the Toyo, Yoko, Dunlop, Bridgestone variety as opposed to Hoosiers / Kumhos, or slicks for that matter. I sort of assume by reading that the Hoosiers / K's are somewhere inbetween normal R-specs and slicks in that they seem to offer a potential faster time but go off much faster. Once I get the dry sump installed later this year I will venture onto slicks, but I'm wondering if I should look at the H/K tyre for now. In effect they sound almost perfect for our events but in reality how long can you get out of them as I will be on at least 285's x 18" rears and they are really expensive down under (approx. $600 US per tyre!). I got almost a whole first season out of my Toyo R888's (update of RA1's) in 2006 and that included some road driving so they are very hardwearing.
Also is the step up to slicks as large as it was to R-specs? Many vendors seem to think that the quality of R-spec has risen so much of late that they're not too far behind the slicks and some of the times are a testament to this.
All advice/opinion appreciated.

EDIT: Found out today that the Hoosiers are a fair bit cheaper than the same sized Toyo's. So I'll probably give them a go, but I still very much welcome an and all opinions.

Geneqco

Patrick, you can usually pick up some slicks with very light useage for very reasonable money if you want to try something out.

From what I'm told, the Hankooks are also much better than the Kuhmos. The Hoosiers can be had for reasonable money but I'm told their sidewall construction is such that they let go quick rather than progressively, not giving you much warning... may be fine once you're used to slicks but perhaps not best for first time experience.

I got my Pirelli's for $100 each... they were really only used for one day for a few laps on a Maseratti with apssengers around Phillip Island, so not driven at the limit. It's worth calling some of the motorsport distributors... at the time Dunlop also had some. From the people i spoke to, concensus seemed to be Pirelli, Michelin, Dunlop, Bridgestone as a good place to start with slicks, although I'm not sure if Bridgestone have slicks readily available here - at least not in 18".

anders44

R spec tires comes in misc form and is road legal, the step over to racing slicks is quite different again. hoosiers etc are not the same as slicks.

333pg333

Well what I meant was that for the moment I will stick to R-spec until the dry sump at least and then maybe try the slicks. So with that in mind I was just curious about the difference between the more standard for want of a better word, R-specs like Toyos, Dunlops, Yokos etc compared to the Hoosiers and the Kumhos. I have read reviews of the H/K type and people say that they are more responsive/sticky but go off after less laps than the others, all things being equal. I spoke to the Hoosier importer today and he seemed to think that some guys in Porsches were getting up to a season of club racing out of a set, but I guess he would say that huh? Also from what I understand they require a more careful run in or heat cycling treatment. Any word on this?
They are actually considerably cheaper than the same sized R888's ($480 vs $630 per tyre! Yes I know we pay much more than you guys yet again...) so that's an extra tyre plus change!

Geneqco

For some of the R-Spec tyres you can specify the tread compound you want that tyre in. From what I understand, if you don't specify, you get the harder compound. For instance, I have Bridgestone RE55s tyres on the Z and there was a choice of 3 or 4 compounds, Dunlop R-Spec tyres offer similar choice. For 4 to 6 laps, the softer compound should be better without getting too hot and "going off". The downside is, they will wear faster due to the softer compound. So you can get softer compound street leagl R-Spec tyres without necessarily goin to Khumo or Hoosiers.

As for Khumos, I've not really had good experiences with them (they were not track tyres)... they tend to get flat spots and then cannot be balanced... tyre places I deal with say they are lagging a bit in the technology department.

I don't have any direct experience with Hoosiers but have been told that they don't really give much warning they are about to let go and then they let go pretty hard... perhaps someone who has used them can confirm this? Do they have a tyre that's street legal here or are you going to take a set to the track with you?

jerome951

333,
I've recently run Toyo RA1s (the predecessor to the R888), Dunlop SuperSport Race, and the Hoosier street-legal (here in the US, at least) road race tire (their last 2 models, not the most recent).

I see about a 2 sec/lap improvement with the Hoo over the RA1 (more over the Dunlop) on a 1:28 course. Pushing really hard, the Hoos will go off, but the RA1s do as well, but to a higher degree. After about 10 heat cycles, the Hoos will begin to slow down but they are still pretty grippy. I find the breakaway characteristics to be about the same between the Hoo and RA1. The Hoo is a little more edgy than the RA1 (i.e. small slips needing corrections) but really isn't that much harder to drive.

I have heard the Hankook (basically an autocross tire) is fast (Hoo also has an auto-x tire) and tend to work at lower temps. In only a 4 lap race, you can't afford to wait until RA1s, Dunlops, or the Hoo road race tire comes up to temp. The auto-x tires may work better for your needs.

I'm warning you, though, running a fresh set of Hoos for the first time is like hitting a crack pipe (so I'm told). You'll be selling or stealing stuff to be able to afford another hit....

anders44

can you use tire heaters before you race ?

333pg333

Thanks Jerome that's just the sort of reply I've been after on a few Forums. Where we are in Sydney it is generally pretty warm most times, but a few times in winter the track was definitely a bit cold to start with. I have found the R888's actually got up to heat pretty quickly and in general have been very happy with them, but you are always looking for an edge and for us we only have to produce one good lap in our club race format so the Hoos are sounding perfect. As Scott says above, I will have to take a spare set of wheels/tyres to the track and that can be difficult. Also I have been running the harder compounds too in the 888's but I have been using them on the road as well. I assume that you can't drive to and from the track with the Hoos without ruining them?
Anders, there's probably nothing to stop us from using tyre heaters, but in general we don't need the extra heat here in Sydney.

jerome951

333, you can use Hoos on the street (a friend drives his 968 from home to events an hour each way) but better hope it doesn't rain on the way. With aggressive neg camber you will wear them out faster.

333pg333

Yeah we're running stupid front camber at the moment. Looks like somethings busted the way it is. May have to dial it back a bit to only -3 or something. Need to dial some more into the rears though. Thanks again for your replies. Helpful.
Patrick

anders44

with uniballs up front you won't need as much camber as the rubber doesn't deflect. you can also try tighening the rear to have less understeer if thats and issue.

333pg333

We found before the last track event that my fronts were not equal neg camber and the one with more neg had a better or more even wear pattern so we brought the other one out to match it. At the event before that I had a bit of turn in hesitation, not quite understeer. So when we changed the fronts to equal big neg the car had much better initial turn in but then wanted to rotate or oversteer. We noticed that the wear on the rears was not evenly spread across both tyres so we will put in some more neg on them and go from there.

anders44

on the smaller tracks we run much more negative camber on left side on car (turning right) to get temps right and that extra ms of time. depends on track really. you should try the new BFG R1 and give me a report on them supposed to be more angry than the hoosiers.

333pg333

Anyone who's used the Hoos followed the run in procedure??
http://www.hoosiertire.com/rrtire.htm

84-944

I love that quote, couldn't be described better! Hey man..."gotta dime?"

Run in helps longevity but we usually just bolt'em on and go.