Autocross tire guys in here please

[blacksheep-1]

So superbeater made it home, now I need to decide what tires to use. In real life, it has to run on 245x17 tires, but under the local rules tires are pretty much whatever you can fit under the fenders. The deciding factor is that they have to be over/under 140 treadwear. I'd like to run Open Mod since they actually start out as cars, but hey need a 140plus TWR.
I'm thinking something in a 295 x 18 on a 10 inch wheel.
since Auto X is not my forte what do you guys know?

 

[blacksheep-1]

OK Bill Pemberton, I know you're out there

 

[boardkat]

For autox...

There aren't any 140/180TW tires I'm aware of quicker than the top tier tires in the 200TW category, although nobody has really tried them seriously due to legality (like the Pilot Sport Cup 2 that comes on the newer GT350). Most likely need a lot more heat to work as well as the 200TW stuff (which generally work in the 120-140deg range). Sub-140TW, the Hoosier A7 is the droid you are looking for.

Dry -
200TW Top Tier: Yokohama A052 > Bridgestone RE71R = BFG Rival S 1.5
*Yoks hate too much heat and need a lot of camber to avoid cording early; they wear quickly regardless though, and are generally the most expensive option unfortunately. But they are the fastest tire available, and put down power better than anything else. Most nationally have been running the RE-71R and Rival S 1.5 for a few years, with each suiting a particular driving style (precision vs. slip angle), and ambient temps (RE-71R work well in cooler conditions, BFGs in hot temps)
200TW Second Tier: Falken RT615K+ > Federal 595RS-RR = Nexen SUR4G > Goodyear Supercar 3 = Michelin PS4S > Dunlop Direzza ZIII > Kumho V720 (non-ACR) > Hankook RS4
*additional note: there is a special tire banned in most series - Kumho V720 ACR, which ran on the last gen Viper ACR. It only comes in two sizes - 295/35/19 and 355/30/19. They're faster than anything above if you can legally run and fit them.

Wet -
Michelin PS4S > Continental ExtremeContact Sport > everything else by a mile
* PS4S can also hang in drying conditions with the top tier dry tires.

 

[blacksheep-1]

the A7s seem a bit hard, as we usually run those in the races..I kmow that goes against conventional wisdom, but we rarely run the R7 compound.
Thanks for the advice eon the Kumhos, we can run them, and I have some experience with them back in the NASA days, I'll check them out

 

[xr7]

I agree in the TW200 range the Bridgestone RE71R, Yokohama A052, and BFG Rival S 1.5 are the best. Falken has a new tire, AZENIS RT660, that has tested well against the top tires but have not seen any in action yet and sizes are limited, nothing for our S197's or s550's. For us middle of the pack guys Falkens and Hankooks are decent enough with good wear.

 

[Grant 302]

I agree in the TW200 range the Bridgestone RE71R, Yokohama A052, and BFG Rival S 1.5 are the best. Falken has a new tire, AZENIS RT660, that has tested well against the top tires but have not seen any in action yet and sizes are limited, nothing for our S197's or s550's. For us middle of the pack guys Falkens and Hankooks are decent enough with good wear.

Would you rank them the same or differently than boardkat? I notice you list the Bridgestone first.

 

[Mad Hatter]

I don't know if you have them in the USA, but the Hankook Ventus TD (Z221) got some great lap times down here... But they dont last very long. Its really a Timeattack tire.

They come in Soft, Softer and Softest...

 

[bob]

Q: wouldn't an ex-heinrocket car be set up well for it's intended purpose T4? Why not do that plus you can't do much in the class but tweek tires and that is your wheel house?

Q: why a 295 on 10" wheel? Isn't it important to support the tire with say 10.5" or even an 11"?

 

[xr7]

Would you rank them the same or differently than boardkat? I notice you list the Bridgestone first.

Seems the quickest guys are running the Bridgestones, Rivals are right there and we have seen few Yoko's, Yoko's reviews on tire wear have most people staying away from them, most of us can't afford burning thru tires. I believe the drivers skill is the biggest factor, only explanation for the time differences with relatively equal equipment. Most of us are just out to have some fun and try not to embarrass ourselves.

 

[Bill Pemberton]

Lots of good data from Boardkat, and the 2019 Nationals saw a lot of guys trying the Yokes. They do heat up fast ,but the question is if you are using for track time and not an Autocross, they might be your last choice of the big three for longevity and time on track. The RE71Rs seem to get greasy a bit sooner than the Rival S 1.5Ss, and for the track that could be your choice. Since you can go with various tires that have at least a 140TWR, you could also look at the Michelin Pilot Sport Cup 2s ( 180 TWR ). Good sneaky idea on the Kumho V720s , though I think the regular ones are not the ticket ( and too small at 265 anyway) , whereas the ACR model is a sleeper with a 200 TWR that is more like 100 , at best. Heh, the rules say over 140TRW and frankly that could be the ultimate sleeper/ legal cheater rubber and they come in .............drum roll .........295/18s.

 

[Grant 302]

Seems the quickest guys are running the Bridgestones, Rivals are right there and we have seen few Yoko's, Yoko's reviews on tire wear have most people staying away from them, most of us can't afford burning thru tires. I believe the drivers skill is the biggest factor, only explanation for the time differences with relatively equal equipment. Most of us are just out to have some fun and try not to embarrass ourselves.

Thanks for clarifying. I have the same three at the top of the list for autoX, but only direct experience with older, now irrelevant versions. And on much lighter platforms.

One speculation I have is that the Bridgestone sidewalls (relatively stiff IMO) make it better for wider than the rim ‘pinched on’ selections/combos. Things I wouldn’t do with say a Michelin (soft sidewall) tire.

And FWIW, I felt the same way about Rs-3s in XL vs. SL sidewalls. Not sure if that carried over to Rs-4s or not.

 

[blacksheep-1]

Q: wouldn't an ex-heinrocket car be set up well for it's intended purpose T4? Why not do that plus you can't do much in the class but tweek tires and that is your wheel house?

Q: why a 295 on 10" wheel? Isn't it important to support the tire with say 10.5" or even an 11"?

I like to autocross, and running that car on 245x17s would never cut it there, nor on trackdays. Don't worry, I'm not going to mess with the basic setup, that would be nuts

 

[drj2k1]

I have to say that my personal experiences fall in line with Boardkat and Bill on this one. Last year running our 8th Gen Civic Si on the National Tour we had two sets of wheels at all events, one set Re71R and a set of Rival 1.5S. With the limited camber allowed on that car (-.7 front) we burnt up both sets by the end of the year running 4 National events and a bunch of locals.

The Bridgestones were more precise and wore better with the stiffer sidewall, also required less warm up time which was important in events up North in a 3 run format. Added benefit of the Bridgestone is you can flip them at half life and get more use from them. I've had 4 sets of these so far and my father's put them on his miata 3x as well (they last forever on that thing). I even bought these again this year for the V6 mustang but haven't mounted them yet.

Rival 1.5S were flat out awesome on concrete and in the heat down at the Match/Champ tour in Tennessee last year (especially in July with a 2 driver car). The slip angles they will take is nuts, which fit my more aggressive FWD driving style. The wear on the other had was not great from my experience due to the soft sidewalls which rolled over at even at very high PSI (255's pinched on a 7 inch wheel lol). They can't really be flipped due to the tread pattern, so once the shoulder was worn they were trash for our use which didn't take very long.

Yokos were proven quick at Nats, but locally I know of a couple drivers who didn't even get a season out of them running even on E-street miatas. Not sure if they can be flipped.

Another option not mentioned yet is the new Federal 595RS-RR Pro. I know the older 595RS-RR was a cheap 200TW option that wasn't too far off the pace of the top tires, but they were VERY loud for street use. The updated "Pro" version is supposed to be much quieter but I haven't seen any data on how they stack up yet. I've been considering picking up a set to experiment on a set of 18x10's to run with the Porsche Club and BMW clubs around here, biggest size I've seen is 275/35/18 though.

Federal 595RS-PRO

Federal 595RS-PRO - Federal Motorsports Competition Tires for Track Days and Endurance Racing - 200 treadwear

philstireservice.com

Looking forward to following your progress with the V6!

 

[Bill Pemberton]

Really excellent thoughts on the ability of being able to flip a tire. The other tire that could be a solid choice in the future is the new Falken RT 660 that is supposed to have some wider tires later this year. It showed pretty well in the TireRack Test and I know the Sales Director there are he is pretty pumped with how the tire ran vs competition and he is an avid Autocrosser ( trophied at Nationals ) himself. One to view in the future, as supposedly will be decent for track work also -- and flippable.

 

[BmacIL]

I haven't personally tried the Yokes, and probably won't unless they make some wide 19" sizes. RE71R are extremely responsive and reward precision. The sidewall is stiff, so they are more tolerant of less than ideal camber, and have great steering weight and feel. They warm up very quickly and are even do really well on damp conditions (standing water, no). In the dry, if you're the type to hang the back end out and steer with lots of throttle, they may not work the best for you. The Rival S 1.5 is very tolerant of high slip angles and takes some heat to warm them up. They felt a lot more sloppy to me than the RE71R, so I didn't like that for my driving style. If you're a 2 driver car, or live in hot climates, they are probably the tire to get.