...yet again on R spec tyres choices.

Ok I have a modified 944 turbo probably weighing in at 2900lbs 1/2 tank no driver.

I can't run Hoosier, BFG R1s, or any other '2 liner' tyre. They put us in with full blown modified GT2s and Cup Cars on slicks by wearing an R6 type tyre. So I'm back to a more traditional DOT drive on the street tyre. I've used R888s and Bridgestone RE55s (which I don't think you guys get).

I want to run about 285-295 x 18 rear and slightly narrower fronts, say 265-275. Our events are like Time Trials and we need a tyre that is going to get up to heat quickly for only 3-4 hotlaps.

Nittos only go up to a 275x18, RA1s the same, Yoko A048 would fit but I've hear varying opinions, Kuhmos no sizes, Dunlops D03? Anyone like Pirelli?

Basically what do you guys think for my situation would be the best? I'm not worried about wet performance or driving on the street.

 

Racing, TT or DE? Different deal. Racers run whatever class and cost allows, TT most fast guys are using both Hoosier and NT01s, forDE wear is the issue.

I would forego the extra 10mm width run a square setup and run the 275/35 18 NT01. They really are the best of the type R's. Don't need to be shaved and easily HC in warm up, so you can use the whole tire, and with a square setup you can flip and rotate to get the most out of a set. The fast TTers go between the nittos and Hoosiers, but the latter HC out quickly by comparison, and then the nittos are faster.

The 44 chassis is pretty amazing and lightened up (2600 w/driver min in 944 spec) and on 225 tires it will run down some fast hardware in the twisties. With the turbo and big tires not too much should get away from you.

 

I hear good things about the Dunlop Star Spec, not sure of sizes. Nitto NT05 is another new tire that I hear good things about. I've tried so many tires and keep coming back to the now discontinued Toyo RA1, thus my stockpiling a couple of sets (and they were 50% off to clear out the warehouse).

I keep hearing about the new Pirelli Trofeo: http://www.pirellityre.com/web/motor...o/default.page

 

It's TT sort of stuff. So 1 outlap 3-4 full sprint laps and then cooldown lap.
I've run 285 f 295 r Hoosier R & A6 before and would love to do the same but I can't. Maybe running the NT01s square is not such a bad idea. I just didn't want to go down too much in size in the rear. Car is probably around 350hp.

I haven't seen those Pirelli Trofeo before. Anyone tried them? What about the Corsas?

 

New tire, thought maybe you had them in Au already. Many loved the Corsa as it was "on" right away and was very good in the rain.

 

Toyo RA1 is coming back into production. 2 corners & they are good to go if you start with them shaved to 4/32".









Professional Racing and Driving Coach

 

It's hard to get a quantifiable answer on the Toyo / Nitto similarities debate. Virtually everyone on here prefer the RA1s to the R888s and say that the NT01 is the same compound. So why are the R888s meant to be so much worse. I've actually used them and thought they were pretty good.

So RA1 vs NT01, what's the verdict?

Also what about some of those V700s in a softer compound. They seem to get a varied response too.

 

What about a Nitto Drag Radial like NT555? How do they differ from a track tyre?

 

IMO the R888's are very good early in their lifecycle. But they have a noticeable drop-off in performance after 8-14 heat cycles, IMO. They they harden up rapidly (sort of like when I think about Danica double declutching...). Whereas the RA1's (and NT01's) will wear to the cords generally before they heat cycle out & harden up.









Professional Racing and Driving Coach

 

Tire life is the big one as is operating range.

My RA-1 lasted twice as long as R888 before they cycled out. That was the same tire size with a focus to optmize the set-up and driving style for R888s.

The RA-1 are also easier to drive. The R888 would overheat if you even had 1 slide. Then the tire rarely recovered during that session. The RA-1 can hold a big slide and if you do they will come back to norrmal by the next lap. So one slide and correct does not kill your race. I had this happen a few time on R888 and it sucked.

However the biggest concern was tire life as the tire cost more than the RA-1 and lasted 1/2 as long. To boot the R888 was no faster than the RA-1.

So R888 was/is a loser all the way round compare the RA-1
- Driveablility RA-1 superior to R888
- Longevity RA-1 superior to R888
- Speed - RA-1 = to R888
- Price RA-1 = R888 (that is new RA-1 price as they used to be cheaper by a few bucks)

That is why NASA and SCCA basicly forced Toyo to go back into production with the RA-1.

I have zero experience on the Nittos.

 

So is the compound the same with the RA1s and R888s?

 

Ok, I can go for 275/295 R888s or 275 all round NT01s. What say ye?
Are these definitely better than the Kuhmo V700s?

Are the NT01s really non directional? They seem to have a distinct pattern that would suggest that they are in fact directional...

 

RA1's and NT01 are non-directional in the DRY. They are directional in the wet.

Nobody really knows the compounds, but the NT01 behave more like the RA1's than do the 888's.

Which to pick? Depends what your tire budget is IMO. The NT01's will have a longer usable life than the 888's, and a square set-up has definite advantages. The 888's will be slightly faster when new, IMO.

Kumho V700's suck, plain & simple.









Professional Racing and Driving Coach

 

Not sure... I have heard many stories. What I know for sure is what I have experienced on track.

 

I agree with everything Joe said comparing the RA1 to the 888. I have 888s on the car now and I do not care for them. Used the RA1 previously and loved them..they were consistant to there death and they lasted forever. Haven't driven the Nittos , but I instructed this past weekend in a race prepped RX8 on Nittos and they seemed to work well. I have heard that on heavier cars the Nittos were a little squirrely. Said complainers were also used to driving on Hoosiers FWIW.