anorexicpoodle

The A052 is the new cheatonium tire. Everyone that weve seen move from RE71R to the A052 is laying down new personal best times.

I have a large amount of AIM data (literally data from nearly everyone in S2K Challenge) and here is what we have found

RS4, Maxxis VR1 are all about equal. Any differences are so small they are plastered over by driver inconsistencies. Like all street tires you get 3 hot laps max before they fall off and need to cool.

RC1/NT01 are about a half second faster than the RS4 but offer the ability to push hard through the session. The tiniest advantage goes to the RC1 in cool weather. We also lump the R888R in here but its slower than both the RC1 and NT01

Nexen SUR4G are a little faster than the RC1. Perhaps a tenth or two but not quite as fast as RE71R

RE71R / BFG Rival S are a half second faster than the RC1/NT01 but wear VERY fast. most drivers saw 3 days on these. We had some drivers claim 4+ but they often didnt run full days so it works out about the same.

A052 is a few tenths faster than the RE71R. We have seen "street tire" lap records shattered with this tire again. Downside to the A052 is its extraordinarily expensive (tire rack has them at $248 each right now, which is hoosier money)

Hankook Z214 / Hoosier R7 / BFG R1 (We lump Toyo RR in here but nobody has data on them) are 1.5-2 sec faster than the RE71R. You CAN drive to the track on some of these (i did on R1's) but itll cost you a heat cycle. Plan on trailering or having someone mule out these on extra wheels.

Unknowns:
Nankang AR1. This is a new one weve seen, that should be 100TW comparable (NT01/RC1) but only one driver has offered input so far
Achilles ATR K-sport. Again weve heard things but havent seen a reliable driver with data show up on them yet.

Nate Tempest

Great info, thank you! Guess I'll see what prices are like up here in Canada for A052 vs RE71R. If that doesn't work out, and I do still want to run a separate set of track wheels, looks like the most logical would be RS4 or maybe SUR4G for economy, ability to drive to/from, and ability to use as a backup AutoX tire if needed. Or if I decide to trailer, could go the other way and look at R7 or R1...

@anorexicpoodle do you know what the wear is like on the fast tires compared to the RE71R? I've heard #s like 25 heat cycles, so if you're doing 5 sessions per day this would be something like 5 track days I guess, assuming you trailer to/from?

I've also heard of using tire warmers to keep them at temp and turn the whole day into once heat cycle, but I assume you'd need powered warmers for that, not just passive blankets.

anorexicpoodle

Life of the race tire vs RE71R is equal if not better. I was able to get 4 competitive days at 4 sessions each on R1. Most guys on the hankooks are getting 4-5 days. Ive not bested 3 days on RE71R yet. After day 3 they could be driven home, but i wouldn't start another day on them.

if you want to drive from/to the best bang for the buck is still the RC1/NT01 by a country mile. You're leaving about a half second on the table over the super-200TW crowd but they will put up 4-5 solid competitive days and usually 2-4 MORE days as scrubs.

Ive never seen anyone at local tracks use tire warmers. Usually they have stiff power needs and the rules of our series actually prohibit them.

Keep in mind when I describe a useful lifespan for a tire, thats the number of days before the tire loses too much time to be competitively viable. I have day 6 and 7 RC1 in my garage that look decent but will be 1.5-2sec off pace. Most of these tires will slow down long before the cord.

Nate Tempest

It would actually be really nice to have a tire that just gets slower as it wears out, rather than the situation with the RE71R where after ~3 days you're wondering whether you could cram in another or if it's going to run out of tread and cut your day short (or worse)!

It is pretty tempting to just go with a second set of wheels and NT01/RC1/even RS4 to start with—the savings in tires would pay for the wheels in under two years. Then when they wear out I could decide if I want to bump up to something faster. (Or maybe there'll be a new magic compound by then, or A052 will be cheaper...)

HawkeyeGeoff

Great info here from very experienced guys. Thanks @anorexicpoodle this was really useful to see a little bit of back to back data.

Nate Tempest

I assume the wear of the Nexen SUR4G is going to be somewhere in-between the NT01/RC1 and the RE71R/Rival S? Looks like I can get them pretty cheap here, and it's nice that they have tread, since on the west coast here we get a lot of track days where there's a chance of rain.

Basically if it's just slightly slower than RE71R and slightly better wear, there's probably not much point in swapping. But if the improvement in wear is more significant than the dropoff in grip I could see it being worth it. Looks like I could pick them up for $160CAD/tire vs $210 or so for the Bridgestones.

Edit: This is a good comparison: https://grassrootsmotorsports.com/ar...-bfgoodrich-a/
Sounds like the SUR4G may actually wear even faster than the RE71R, so despite its lower price it's probably not the tire I'm looking for.

ncrx

the sur4g is terrible in the rain compared to the re71

Xene

If you can afford, I would have 2 sets of wheels. One set with RE71R just meant for setting laps times or autocross. Have a second set with RS4s just for practicing on track. When your ready to set a lap time put on the RE71Rs

anorexicpoodle

FWIW This is a both a PITA and a surefire way to handicap yourself if you're not an experienced driver that can adapt quickly.

Half of a faster tire is knowing that you can use the additional limits the tire offers you, then doing it. The RE71R might offer you the ability to enter corners 1-2 mph faster because it will hold the speed over the RS4, but if you practice on RS4 you're teaching your brain to hit brake markers a smidge earlier and stay on the pedal a little longer. It takes even the most experienced drivers I know a lap or two to familiarize themselves with a new tire, and a full session to dial pressures for a solid run.

My advice is pick your tire, and use only that tire for a while. Minimize variables so you can tell the difference between you getting better and just bolting time onto the car. Ive seen tons of guys stuck in the 59's at buttonwillow, bolt on RE71R, a new splitter and a bigger wing then strut around with their 58 like they are Ayrton Senna.

Seat time over compound. Buying a little time now will hurt you more in the long run.

If you feel like you need to spend the money, take the money you were going to spend on a 2nd set of wheels and get a data system. The data system will make you better than any tire could.

Nate Tempest

That's an interesting perspective. I can certainly see how if the goal were time trials, you'd want to practice on the same tire you race on. And I absolutely agree with you want to be data driven and consistent, rather than just trying to buy faster times.

For me, the primary competitive goal is autocross; I do about 12 autocross events per year, and want to be as fast as possible, so I'll definitely be sticking with the RE71R there, until something faster comes along. For track days (about 5-6/year), it's not so much that I want a faster tire; it's that I don't want to keep burning through my autocross tires so quickly, and having to worry about managing them. So I was thinking a separate set of wheels and tires for track days would actually be more convenient, even with switching. (I already like to check the brake pads and burp the calipers between track days, so swapping wheels wouldn't be too much extra...) And if I got something like NT01, the wheels would pay for themselves pretty quickly in the tire savings. (Of course, like anyone I enjoy going fast, so the temptation is there to try out a faster tire too, since I can... I think I can resist it for now though.)

Since autocross and lapping are pretty different already, I don't think using a different tire would throw off my internal calibration, although I guess I could be wrong! As far as data, I do use a budget approach right now and find it indispensable. I have a 10Hz bluetooth GPS unit and a bluetooth OBD reader connected to either Racechrono Pro (for lapping) or SoloStorm (for autocross) on my phone. (And as an aside, I rely on this much more than feel for braking points when lapping; I start out conservative and then gradually adjust later while watching my deltas. It's also great for experimenting with slightly different lines.) Also use a pyrometer to manually check tire cross section temperatures. I'm sure an AIM system or something would be better for the track, although I'm not convinced it would be enough better to be worth the significantly greater expense. (Would it?) And for autocross SoloStorm is pretty great since it's designed specifically for it.