200TW HPDE tire selections (with one condition)

[ChrisAttebery]

That's interesting. Is the upper group supposed to be faster than the lower group? Some of the lower group may be faster over 1 lap but not as fast over a whole session. From what I've read the RS4s, Direzza 3s, Vr730s and CR-1s are probably slower than some of the tires in the upper group.

I've read Grassroots Motorsports' tests and they probably wouldn't agree with some of those groupings.

 

[victorofhavoc]

There are several factors in their decision making. I will say that the nt01 isn't necessarily a faster tire than ps4s. It can be more consistent, but for a hot lap (and especially considering a season of driving with variable weather) I think those groupings are fairly accurate. My best street tire time was on the yoko a052. Nothing 100tw+ can touch that tire for a hot lap, but after 3 laps it's grease city and after 12 sessions they're trashed.

The upper group is intended to be slower than the bottom group. What's insane is you can run a stage 2 gti in the tt5 group if you run a tire from the top group. Running a tire from the bottom group my stage 2 gti has passed tt5 and some TT4 cars pretty quickly, but it certainly doesn't come close to keeping up with a tt3 car. With a ps4s or one of the "old" 100tw from the top group it should be very competitive in tt5, as long as you have the dsg. Gearing and low speed corners favor dsg a good amount... And there's an updated modifier to account for it as well (because the tcr cars were trashing everyone in high spec cars).

A big factor is that this is club racing and not pro. While some people are certainly capable of plonking down $1k for tires each weekend to get the fastest times out, most people are money conscious. The groupings partially reflect this to account for those who will run one or two sets for a season rather than 6-10 sets.

Everyone has been unhappy with these rule changes, which means they're most likely fair!

 

[ChrisAttebery]

The NT-01 and a few of the Toyos are using pretty old compounds. They are somewhere between the hot 200TW tires (A052s) and the endurance 200TWs (RS4s). The funny thing is the Nankang AR-1 and CR-1s seemed to be flipped compared to GRM's results.

GRM Ultimate track tire guide

 

[victorofhavoc]

The NT-01 and a few of the Toyos are using pretty old compounds. They are somewhere between the hot 200TW tires (A052s) and the endurance 200TWs (RS4s). The funny thing is the Nankang AR-1 and CR-1s seemed to be flipped compared to GRM's results.

GRM Ultimate track tire guide

Totally!

I think this is partially due to the fact that the ar1 requires good heat before it grips while the cr1 is ready to roll off the line. In the tt4 and lower groups there aren't as many significant cooling and power cars that would be able to actually heat up the tire enough to grip before everything else is overheated (like brakes, iat, and water/oil). In TT people focus on the first 4 laps and the rest of the time on track is just keeping heat at bay and learning new things.

 

[Mini7]

I was looking at the TT4 regulations the other day the tire modifier makes no sense to me. Why would a 100 treadwear NT01 be in the same category as a 300tw PS4S?? And the Maxxis RC-1 is pretty much a slick with two grooves.

I’m a big fan of NT01’s for there performance vs wear. The MPS4 and NT01 are closer in performance than one might think. Once I was able to get NT01 tire pressures dialed in I was able to create some separation in lap time.

Looking at the list I have a hard time see the R888R’s and Toyo RR’s being on the same list. I had a hard time extracting speed out of the R888R’s. With my driving style anyway.

I'm curious whether the new Continent Extreme Force will be the new NT01 but faster.

 

[GTIfan99]

I’m a big fan of NT01’s for there performance vs wear. The MPS4 and NT01 are closer in performance than one might think. Once I was able to get NT01 tire pressures dialed in I was able to create some separation in lap time.

Looking at the list I have a hard time see the R888R’s and Toyo RR’s being on the same list. I had a hard time extracting speed out of the R888R’s. With my driving style anyway.

I'm curious whether the new Continent Extreme Force will be the new NT01 but faster.

What did you end up running for pressures with the NT01?

 

[Mini7]

I need to check my notes. Nitto called for 38psi hot but I found that 34-36psi worked better.

 

[GTIfan99]

I've been running RE71R's since they came out on my cars, now moving to V730's. It'll be interesting to see if they need more or less pressure, I'm guessing more.

The stones hot could be run as low as 26 psi in the Miata, but needed at least 37 - 38 at the front of the GTI to keep from rolling over on the sidewalls. I'm a little worried that none of the current super 200's have the sidewalls of the stones, so the feel and setup is going to take some time to dial in.

 

[krs]

Running my V730’s the last 2 events had about 2 psi higher than the Bridgestones.
But I can’t say I have enough time them to feel I have that dialed in yet.

 

[GTIfan99]

Running my V730’s the last 2 events had about 2 psi higher than the Bridgestones.
But I can’t say I have enough time them to feel I have that dialed in yet.

And what was that hot?

 

[krs]

And what was that hot?

Las Vegas - 1 - 54°
39 psi front, 41 psi rear for the 3 best runs I had.

 

[victorofhavoc]

Do you guys make alignment adjustments when moving to a new tire?

 

[GTIfan99]

Las Vegas - 1 - 54°
39 psi front, 41 psi rear for the 3 best runs I had.

Awesome, that's exactly what I was looking at starting at.

 

[krs]

Do you guys make alignment adjustments when moving to a new tire?

I never have, I just throw the new ones on and go.

 

[jimlloyd40]

Do you guys make alignment adjustments when moving to a new tire?

Shouldn't have to just for new tires. I never have and it didn't affect tire wear. Speaking about street driving.