street stock tires

[nateh]

We'll all be looking forward to meeting you at the track!

[DanB]

I think that a street tire rule for Showroom Stock makes a lot of sense. For one thing, the grip level is more suited to the suspension.
For another, it would be good, I think, to have an "arrive and drive" class. IMO, this would encourage more participation from people who don't want to be at a competitive disadvantage but don't want to spend the extra $$$$ on an extra set of wheels and race tires and/or don't have a way to get them to the track.

As for enforcement, this would depend on a competitor protesting, just like almost any other infraction. Tech wouldn't "catch" an aftermarket cam either, someone would have to protest.

Regarding the time differential guessed at above, the difference around most road courses will likely be LESS than it is at autocross competition. In autocross you're *always* cornering/braking/accelerating at the limits of adhesion. At the road course, only part of the time.

For reference, I did a 2:20.5 at Watkins Glen in my stock S2000 on 225/50-16F//245/45-16R Kumho VictoRacer R-compounds in '07, and I did a 2:21.4 there this year on 205/55-16F//225/50-16R Dunlop StarSpec and Sport Maxx TT street tires. Granted, Victoracers aren't the grippiest R-comps, but still I wouldn't expect the difference to be any more than 2 seconds at most tracks we run.

[Track wheels]

and I acknowledge this time advantage is always going to be
hard to set.
There could be a bigger difference when higher horse powered cars with serious factory stock settings multiply
the extra grip that a hoosier supports.
I`ve seen highly trained drivers exploit the extra grip and cut their times by a huge amount without the power but
their suspensions were full race level.
Most of the seasoned, long term drivers on Hoosiers, are not going to allow a driver to beat them with a made up time advantage.
What might work is to just give an official notice of record if their time places them - with an agreed time advantage -
within the top placers.
Over time, if there is an interest in this, it might develop as a separate set of awards for non-Dot Rated rubber
for the real lazy cheap guys, who want bragging rights in the daily driver category.

[betelgeuse]

and I acknowledge this time advantage is always going to be
hard to set.
There could be a bigger difference when higher horse powered cars with serious factory stock settings multiply
the extra grip that a hoosier supports.
I`ve seen highly trained drivers exploit the extra grip and cut their times by a huge amount without the power but
their suspensions were full race level.
Most of the seasoned, long term drivers on Hoosiers, are not going to allow a driver to beat them with a made up time advantage.
What might work is to just give an official notice of record if their time places them - with an agreed time advantage -
within the top placers.
Over time, if there is an interest in this, it might develop as a separate set of awards for non-Dot Rated rubber
for the real lazy cheap guys, who want bragging rights in the daily driver category.

I wish you would stop talking about some kind of hadicap system because it probably is'nt going to happen.

You have a BMW 135i... correct? That car should be top dog in SSGT even on street tires. You worry too much. If you can drive good enough you will win. It's as simple as that. There are quite a few BMW guys in the club that would be more than happy to help you with your driving or anything else you might need. Just sign up, show up, drive and have fun.

Greg

[Track wheels]

I Agee. Read my notes and you can see, I am not going to
Submit a rule change until I get some time in TT.
I got my licence a few months back
But my car was sidelined since, due to brake repairs.
I still think it's an interesting idea but there is other things
I'm I looking into -
Like maybe an R compound that can be left on the car
But still be ok as a daily driver if it rains
I'm wondering if someone has some ideas.
I am already missing the track and planning for next spring

[blindsidefive0]

Wow - heated conversation... I have a nice set of Kuhmo v710s for next year, but would love to just run some nice street tires (one set of wheels) after those are gone.

Anyway, some tire recommendations. Dan Baldwin already mentioned a good one...

Street tires:
- Dunlop Direzza Z1 Star Spec - really good in the rain, almost as grippy as some slower r-compound tires in the dry (if they are new and shaved), I know a lot of guys who run this for autocross
- Hankook Ventus R-S3 - tread wear rating of 140 and insanely cheap
- Kuhmo Ecsta XS - tread wear of 180, also very cheap

If you want to keep one set of wheels and run r-compounds, probably the Toyo RA-1, Toyo RA-888, or Nitto NT-01 are your best bets. I think the R888 is the best in the rain, but none of them should heat cycle themselves from highway driving. Hoosier R6/A6, BFG R-1, Kuhmo v710, Hankook c214 are all technically DOT, but they will heat cycle on long drives, reducing their life at the track.

[jeffw]

If you want to keep one set of wheels and run r-compounds, probably the Toyo RA-1, Toyo RA-888, or Nitto NT-01 are your best bets. I think the R888 is the best in the rain

have you actually run the R888 in the wet? It seemed terrible to me compared to the RA1.

[WillM]

Like maybe an R compound that can be left on the car
But still be ok as a daily driver if it rains
I'm wondering if someone has some ideas.

I really think this is a bad idea (To run r-compounds on the street for daily driving).

I would stick with one of choices in Tire Rack's "Extreme Performance Summer" or "Max Performance Summer" categories. Seems that the Continental ExtremeContact DW would be a great choice for combined daily-driving and track day use, in wet and dry conditions alike. I have Hankook RS-3 tires on my summer/fun car, and bet they would be great on track too. Actually, it is possible the the LeMons car I ran was on the RS-2 or RS-3 tires, and they felt pretty damn good.

[Track wheels]

I was just talking to Jeff W. an instructor ,who was very helpful
Last Sept at WGI,about leaving RA-1s on all the time,
And you stopped me from making this mistake.
I had no idea the highway could heat cycle the tire.
I've also read that some new tires have to be heat cycled
to get them to really stick.

[Track wheels]

I leave my Dunlop Z-1s on always and they don't run anything
like they did in the first few days.

[CP]

have you actually run the R888 in the wet? It seemed terrible to me compared to the RA1.

I have heard the same thing from multiple racers and is one of the reasons why I never even wanted to try the 888 last season while it AND the RA1s were both legal to run for SCCA SM. The 888 has a much stiffer sidewall (better initial turn-in), wears twice as fast (on a Spec Miata) and sucks in the wet compared to the RA1. It also likes MUCH lower hot pressures. These are several reasons why it was phased out of Spec racing less than 12 months after it was introduced.

[6PAK72]

Jeff W,

What did we run the CrapCan Lemons car on?

You and John were turning eye-watering fast laps.

I like the idea of a run what you brung class. The TR6 would do well

And, I still vote for the BF Goodrich Comp TA's, especially since the compound has been revised to a lower wear rating - they feel fantastic.

[joncowen]

I leave my Dunlop Z-1s on always and they don't run anything
like they did in the first few days.

Are these star specs? I run star specs on my M3, and they are fantastic on the track all the way down to the wear bars. On my last set, i used them up at an open lapping day at NHMS, and found that i was running similar or better times then when they were new.

One thing with the star specs- when they are newish, with lots of tread, they get warm much quicker, even at lower pressures. I found that they seemed to like a higher pressure when they were worn past 50%.

[jeffw]

Jeff W,

What did we run the CrapCan Lemons car on?

You and John were turning eye-watering fast laps.

They were the direzza star specs...they felt great!

[blindsidefive0]

Admittedly, I have not driven r888's in the rain. This just comes from research before buying the NT-01's for the 964. My cousin who runs NASA with a C5 recommended them in the wet - Toyo sponsors NASA so I guess a bunch of guys run the RA-1 and 888. I've also seen some negative reviews for the r888, but a lot of times these have been from drivers or lightweight cars (miatas, mostly) with camber setups for the RA-1 - apparently the r888 needs less negative camber, so sometimes the inside tread can wear and cause poor traction, especially in the rain. However, on larger cars (like M3, 911, 350z) with the right setup people seem happy (BMW, PCA forums). I have run the NT-01s in the damp (same compound and construction as r888) and they are pretty good, but everything I read indicated that the r888 has a more favorable tread pattern in deeper water compared to the NT-01, and they didn't need to be shaved to reduce tread flex (compared to RA-1). The only reason we ended up going with the Nitto was $$$.

As far as heat cycling on the street - Dave and I picked up some v710s that hadn't been properly heat cycled. We drove them on the highway for a couple hours straight, but couldn't really get them hot enough. We used a pyrometer which isn't perfect, but you can at least get a ballpark (i.e. are these tires even warm?). I've read that the Toyo's are even less susceptible to heat cycling out than v710s or R6's, and that seems to be the case with the Nittos (same compound). I haven't tried this, but I've read that a bunch of people (and heard from NASA and autox drivers) don't worry about driving this compound to/from the track, and have been able to drive the tire down to the cords without heat cycling out.

Anyway, my $0.02 - tire debates are like politics so I'm sure others will have strong opinions, especially for rubber they currently/previously own...and like I've said before, I'm happy to be educated if someone thinks my summary is "wrong"