Track tire decisions

[OldFaithful]

Originally Posted by Grip Addict

Glad to see some RE-71R discussions.

I need new tires for my summer set and have been plotting splurging and getting a really grippy tire for my daily E92 M3. The car gets 1-2 track days a year. More likely 1 roll race/drag day and a road course day.

I could not get definite answers on how long the tire would last.

I need it to last roughly 15-20k miles with the 1-2 track days a year? Possible? or near possible?

You already started a thread asking how long RE71R would last and you weren't able to get a definite answer because THERE ISN'T ONE. No one knows what your driving style is, how heavy your car is, what your alignment specs are, what temperatures/pressures you will be setting the tires to, etc. and how each factor will affect the tire wear on your car. The only way for you to know how long they will last is to try it and find out.

[rhyary]

Originally Posted by lutfy

I've seen your car I used to run TTD (now TT5) with Nasa MA.

I purchased a set of (new) tires to test 2017. RE71R, RR, R888R, Hoosier R7


I put on a set of RR and they were fast for 4-5 laps, then they drop off. The RE71 was 1/2 sec quicker (same day...) if anything they were almost a few tenths off 14 heat cycled R7. It could be that the R7 was 225/40 (shorter) tire compared to 245/40 RE71R.

For the money, cant beat RE71R. I wouldnt touch RR unless series allow them, they are not that much quicker than the R888R if that. RE71R acts closer to R7 (when they let go) vs howling and screaming like the Toyos.

At road atlanta in 2017 I took both my RR (5-6 HC) and R7 (brand new) and the difference was 3 seconds (not a typo) in TT same day.

Cheers,

Lutfy

.
I just purchased a season worth of RR.
Since I have to use 19" my choice up front is not ideal. I have to go with the RR 235/35/19.

While last year I tried them as an experiment, among many other tires, I decided to commit to these tires and get the most out of them.

The fact was that last year, at NYST I did ~20 track days, the RR were the fastest, beating all the other tires I tried.

While I experimented with 265/30/19 and 275/30/19 up front the 235/35/19 had the best grip.

Why that is, is difficult for me to analyze, but I don't think it is only due to the slick tread.

I think it is also track dependent. So on 18-turns track with a very high grip, it is possible that the 235/35 is getting more rubber on the road just because it is narrow.

I did experiment with hot PSI and the upper range of 36-38 helps with even wear. the M3 is heavy and I think this tire was designed for the Miata.

In my experience, The RR were a second faster than the R888R. with the 265/30/19 up front I was laboring to stay in 1:38 at NYST, with the RR i was at 1:37 in the first session on them.

Longevity was about the same.

The price is right.
.

[bigjae1976]

Originally Posted by SYT_Shadow

I'd add to NT01 comments:
-Makes infernal noise on the highway. You may decide life is not worth living prior to reaching the track
-Has splicing issues to this day which may ruin your track weekend at any time
-Cannot really be used to drive on the street as they are terrible in rain
-Driven fast, last just as long as RE71R

I love the noise! Lol

I think the tread splice issue isn't really an issue any more. But I think nowadays, there are other options out there to the NT01.

I like the NT01 for hooning!

[bigjae1976]

Originally Posted by dparm

I suspect the NT01 is still the more aggressive tire, but the Rivals seem to actually provide some level of traction in the wet whereas the NT01 looks like it won't...

The NT01s are decent as long as there are no puddles or rivers and you can keep heat in the tire. I'd never drive them on the street if the pavement was even damp.

[Grip Addict]

So interesting I just tried to pull the trigger on the RE-71Rs from Tire Rack. They called 20 minutes later to warn that they do not meet the load requirements of my M3.

[ThunderMoose]

Originally Posted by Grip Addict

So interesting I just tried to pull the trigger on the RE-71Rs from Tire Rack. They called 20 minutes later to warn that they do not meet the load requirements of my M3.

You never I repeat never say what car you are buying tires for.

[SYT_Shadow]

Originally Posted by ThunderMoose

You never I repeat never say what car you are buying tires for.

I was going to write the same thing

[Grip Addict]

Originally Posted by ThunderMoose

You never I repeat never say what car you are buying tires for.

Care to share reasons why?

[slicer]

Originally Posted by Grip Addict

Care to share reasons why?

Because they always delay order until you confirm unless you buy a factory tire in a factory size.

I put in comments "Tire fits my car. Release order"

[bigjae1976]

Originally Posted by Grip Addict

Care to share reasons why?

Many times, extreme performance or r-comps have a lower load rating than the OEM tire. That may cause a flag. For example, Discount Tires won't even sell or mount NT01s if they know that its going on my E90 M3. Its a perceived safety and liability issue. Which is actually an issue fitting larger/heavier cars, SUVs or trucks with tires.

To be fair, most tire customers aren't using them for track use and its an employee following a policy.

[VictorH]

Running track event at VIR this weekend and running RE-71R in 255 in front and 275 rear. Two of the three sessions today were in the rain and the last session was really raining hard. The surprising thing is how good these tires are in the rain. The grip is really quite good. I lowered the pressure to 28 psi to start for a bit more contact patch and after the session they had warmed up all the way to 30 psi (sarcasm ). Was running 135 mph on the back straight and 120 on front in the rain with no hydroplaning and in fact was able to out-brake quite a few other drivers. I like the rain though and I think some of the other folks in my run group were a bit tenuous.

I'm not sure what other street tire I would change to from this after this set is worn out. For my combo -3.0 negative camber in front and -1.75 in the back gives nice even wear. Can't complain super tractable.

[Grip Addict]

Originally Posted by bigjae1976

Many times, extreme performance or r-comps have a lower load rating than the OEM tire. That may cause a flag. For example, Discount Tires won't even sell or mount NT01s if they know that its going on my E90 M3. Its a perceived safety and liability issue. Which is actually an issue fitting larger/heavier cars, SUVs or trucks with tires.

To be fair, most tire customers aren't using them for track use and its an employee following a policy.

Right, to continue to be fair. I would use them for one, maybe two track days a year. Means the "employee policy" probably saved me from whatever potential issues not following a load rating can occur.

[bigjae1976]

Originally Posted by Grip Addict

Right, to continue to be fair. I would use them for one, maybe two track days a year. Means the "employee policy" probably saved me from whatever potential issues not following a load rating can occur.

You'd probably be ok with the RE71s unless you drive the car near its max gross weight. I'd bet that there is some safety margin even if you did.

The tire shops do that protect the uneducated consumer which is 99.99% of the people that come in and buy tires.

[Dreamer99]

After reading through a bunch of posts on the RE71R it looks like 38psi hot is the goal. So starting around 28-29 psi is where I should start. Does this number change depending on the air temperature? Or the tires usually gain about 10psi when driven hard?

[SYT_Shadow]

Originally Posted by Dreamer99

After reading through a bunch of posts on the RE71R it looks like 38psi hot is the goal. So starting around 28-29 psi is where I should start. Does this number change depending on the air temperature? Or the tires usually gain about 10psi when driven hard?

Starting at 28-29 is a really good base assumption

[SYT_Shadow]

Originally Posted by VictorH

Running track event at VIR this weekend and running RE-71R in 255 in front and 275 rear. Two of the three sessions today were in the rain and the last session was really raining hard. The surprising thing is how good these tires are in the rain. The grip is really quite good. I lowered the pressure to 28 psi to start for a bit more contact patch and after the session they had warmed up all the way to 30 psi (sarcasm ). Was running 135 mph on the back straight and 120 on front in the rain with no hydroplaning and in fact was able to out-brake quite a few other drivers. I like the rain though and I think some of the other folks in my run group were a bit tenuous.

I'm not sure what other street tire I would change to from this after this set is worn out. For my combo -3.0 negative camber in front and -1.75 in the back gives nice even wear. Can't complain super tractable.

I haven't tried anything as nice and tractable as the RE71 as a dual purpose tire

[Dreamer99]

I've got my RE71R's all mounted and ready to go. Thanks for everyone's input. First track day is April 20. Can't wait! Question though, do theses tires have to be stored in a heated garage like a true R compound? It still gets below freezing here and my shed is not heated.

[VictorH]

The RE-71R is a really great tire. The grip seems to hold up really well throughout a session, though track temps were low where I was.

Couple of tire observations:
RE-71R nothing more needs to be said, they are a bit noisy on the freeway though, particularly compared to Super Sports or the new 4S from Michelin.

Michelin Sport Cup 2's- These are a really good tire. I think perhaps the early generation might have had issues. I've never owned a set but my neighbor runs SC2s on his GT350 and after a fair amount of fiddling to get the right suspension set up on his car, they are pretty incredible. Drove his car for one session on Saturday in the dry, about mid 50sF. The grip is tremendous and they squeal just like regular tires as you approach the limit. The are tire pressure sensitive and you don't want to run them too high, maybe 35psi max. Another driver next to us had Sport Cup 2s on his Porsche, much lighter car of course, but he had 9 track days on his tires nd they have made a round trip to Watkins Glen and back and still looked perfectly reasonable. Not sure why this tire got such a bad rap but I think the new generation is really quite good.

Has anyone heard about a new Sport Cup 2 coming out? someone mentioned this at the track yesterday.

[SYT_Shadow]

Originally Posted by Dreamer99

I've got my RE71R's all mounted and ready to go. Thanks for everyone's input. First track day is April 20. Can't wait! Question though, do theses tires have to be stored in a heated garage like a true R compound? It still gets below freezing here and my shed is not heated.

No need to store it differently than a regular tire

[dparm]

Originally Posted by VictorH

Has anyone heard about a new Sport Cup 2 coming out? someone mentioned this at the track yesterday.

The new one is the Sport Cup 2R, which is basically a "cheater" race tire.

https://www.tirerack.com/tires/tires...+Sport+Cup+2+R

https://rennlist.com/forums/991-gt3-...ally-here.html


Per the above Rennlist discussion, it's basically the Cup 2 with a race compound 1 or 2mm thick to set really fast lap times.


CJ is correct. We had Porsche and Michelin guys recently at NCM to re-set the lap record on a fresh set of Cup2R. The recent Automobile review with ZR1, GT2RS, and McLaren 720S where the GT2RS turned a 2:05 was on a "worn" out set of Cup2R tires with 8-10 cycles on them. The first 1-2MM of tread is literally their race rubber, after that is worn way, it is their normal Cup2 rubber. That is how they get their 150 rating, because it's not race rubber for the whole tire. So once you wear away the first 1-2mm, the super sticky race rubber is gone. Porsche showed up again with a brand new set and ran a 2:02.XX at NCM with the set of sticker Cup2R.

That's how they work, and why they are so crazy expensive. Literally two different compounds, same tire. Interesting, but doesn't make much sense to me for the cost. I'll take Trofeo-R all day long, still faster than Cup2 N1, and barely more expensive, and almost half the cost of Cup2R.


Also from the Rennlist thread:

I used now 3 complete set of cup R on my gt2 rs so i can tell you the truth:

this tire is like a slick, i don’t know if there is 2/3/4mm of high grip gum on it but what i can say is that they are optimal for 100/150kms of track use, it will works better/faster on this car vs a real slick in 19’ size that you can’t find on size 325 mm rear on the gt2/3 rs

what happen after 150kms on the track....:it still works!!!....but offcourse less good and this is the same on trofeo R or normal cup, the difference of grip is just more significant because yes the grip when it is new is far better than these two.

you can use the cup r all the day on the track but on the afternnon you will be slower, i can extrapolate:

My feeling is
on a magny cours GP track a 5.3kms track in france for exemple with a stock gt2 rs correctly adjusted (camber, heigh of suspension etc...) :

cup R new: 1.45min
trofeo r new: 1.47min
cup2 new: 1.48.50min

Cup r after 150kms: 1.48min
trofeo r after 150kms: 1.49.50min
cup2 after 150kms: 1.49.50min

cup r at the end of the day 350kms: 1min52
trofeo r at the end of the day 350kms: 1min52
cup 2 at the end of the day 350kms: 1min52.50

So yes this tire must be reserved for a beautiful occasion, on a beautiful race track, with beautiful friends and cars to play (or destroy and beautiful weather/temps conditions to maximize the driving pleasure

if these conditions aren’t collected, keep the regular cup 2 or the trofeo r, just price reminder gt2/3 rs here in france:

cup R: 3000€
trofeo R:1900€
cup 2: 1500€

It is comparable for me to eat in a 5* 3month reservation required restaurant and eat in a good familial food restaurant, both are great it depend of the occasion and your spirit on that day ����

[bimmerboyE92]

How are you guys getting your RE71s to last? Mine went 4 days with 4 30min sessions per day in intermediate.

[VictorH]

Originally Posted by bimmerboyE92

How are you guys getting your RE71s to last? Mine went 4 days with 4 30min sessions per day in intermediate.

Wow! That's really low. No one can say for sure without seeing your car set up, including alignment and how you drive. For most of us finding the "optimal" alignment set up requires a lot of trial and error. It's not practical to go to the alignment shop each time, you'll need some way to measure camber and toe (doesn't need to be super accurate) to get you in the ball park and then if you can go to aligment shop to check and then mark your settings.

Needless to say the driver is the other huge variable. I've had a retired pro driver run my front tires down to the cords in one 45 minute session, when I thought I had a couple of weekends left on them (had checked them that AM). Yes, we were going very quickly. At your next track event, ask an experienced driver to ride with you, ask around, have someone look at your tire wear. The answer will become clear with some investigation. It's almost certainly not the tires themselves.