S2K - road tire recommendations please

[NecronomiconJules]

Hi all,

 

looking to get new tires for my Ultralite. Note: S2Ks wear larger tire diameter (~ 25 in), thus heavier wheels, than other 7s.

 

I live in California - no need for rain compound - and drive my car exclusively on dry public roads.

 

First time I bought a new set I chose Pirelli Trofeo R in 225/45-17 front, 255/40-17 rear. Rave reviews, allegedly faster (and actually lighter) than R888s or NT01s, etc. Experimenting with pressure I got it down to 17-18 lb/in.

 

Well, it's been strangely disappointing. Grip all too easily overcome at the rear, little feedback from the front, not to mention a couple of snap oversteer episodes in circumstances and at speeds that would not phase my VW Jetta one bit.

 

Not enough heat, perhaps, or sidewall too stiff for the load? What I'm looking for is a set that delivers what I was hoping to find in the Pirellis: great grip, progressiveness & feedback.

 

Ideas? Recommendations?

 

Thanks.

Eric

[MudHut]

I'm running NT01's in the same size you mention. The Nitto's will probably will heat cycle out and become hard before they wear out considering the cars weight. They tend to get sticky when run hard but that's not a bad thing I suppose, although they sling rocks into the cabin. I haven't had them get greasy feeling like Hoosiers when hot, hot.

I'm running 600/500 lb springs so a lower air pressure works well on mine. Nitto's aren't too pricey and are my current favorite.

 

Jay

[rnr]

I also ran NT01s in that size on my Ultralite and was very happy with them. Originally started wit 235/275 but I had trouble getting them to temp on cold track days. The 225/255 warmed up nicely and gave a decent ride. That said I used to run at 14 PSI hot for optimal grip and ride. The Trofeo is the spec tire for Lambos and other supercars so its probably designed to work best with 3000+ lbs cars. I would try dropping the pressures some more before pronouncing final judgement on them.

[m wirth]

Hello, I have had good luck with the Faulken 615k, 225 front 245 rear for the street. I run the same size in Nitto NT 01 for track days, both sets are mounted on light weight Enkei wheels. I have been lucky at several track days that the promoter has dedicated personnel to take tire temps immediately after a session and have found that at ORP and The Ridge they recommended 26 psi front and rear, this pressure yielded only a 2 degree difference across the tires, I did notice a difference especially in the off camber corners at ORP. I run the same pressure on the street in the Faulkens.

[rnr]

have found that at ORP and The Ridge they recommended 26 psi front and rear.

 

What spring rates are your runing on your car? I ran my S2k at 22 psi the first day I had it and the vibration was truly brutal. I had to get it down to the teens before it was tolerable on the street.

[NecronomiconJules]

Thanks all. So, NT01s in good standing so far. Falkens well reviewed too. I liked the Nittos on my late 911 but that was a barge of a thing in comparison - no issue generating heat.

 

Speaking of spring rates: rear grip is so easily defeated that in addition to lower pressure, the alignment shop recommended softer spring rates: 200 front, 160 rear. It does help, just not enough, so back on the subject of tires. Here's a selection that this and other (UK) forums speak favorably of. Keeping in mind that this is primarily for dry street driving, how would we grade them?

- Azenis RT615K

- Toyo RA1

- Toyo R888/R888r

- Advan A048

- Nitto NT01

- Avon ZZR

- [you fav tire name here]

 

Eric

[m wirth]

Hi rnr, my front spring rate is 400# the rears I don't know since the stamping was so light I could not read even with dyeing it and a mag glass. I have never had a vibration on street or track, car tracks great. -1 1/2 camber FandR , 1/16 toe front and 0 rear ( 0 toe was too quick for me ) I am still running QA shocks but have changed the damping to heavier rebound, settles in the corners better. My car hooks up great out of the corners with minimal if any wheel spin. I run a 3.90 viscous LSD not a 4.11 which may induce more wheel spin also if it is open. I am building another 3.90 LSD with a Cusco unit in it. It takes a while to learn your car and how to carry speed without using the throttle as much, I now have over 3,000 miles of track use and I'm still a beginner compared to some of the people I run with.

[powderbrake]

I am running Falken 615k. I run 20 psi on the street, 14 psi on the track.

I have 1/16 front toe, -1/4 deg front camber, 0 rear toe, -1 deg rear camber, 4 deg caster.

QA 1 shocks, 400# fronts, 300# rear

[jimrankin]

I run the NTO1's as my street tire but had also used my previous set as my track and street tire. I love the NT's as a street tire as when you get them down to about 16-17 Lbs they both stick and take up a lot of the road surface bumps with no adverse effects from the low pressure.

The first set of NT's held their grip (didn't heat cycle out) after way over 20 track days and had a lot of tread left when I replaced them with slicks. I liked them so well I bought a new set for my street tires but probably could have just kept the old ones as here in CA we don't have to deal with getting caught out in the rain and they were still gripping even though well below the wear bars.