Hoosier - A6 or R6?

[260DET]

For circuit time attack, one warm up lap followed by five hot laps at the most in avatar car. Must be my driving style but I regularly have trouble getting semi slicks up to temp, the ones that worked best were Toyo RA1's but they are no longer available.

 

So to anyone who has used Hoosiers, your opinion plus a brief description of what circumstances they have been used in. Its my understanding that the A6 is what we would call a hillclimb tyre, no warm up required which indicates two circuit laps at most. But?????

 

And if you have time to waste here is a sample of the application

[heavy85]

Around here A6 rule hands down. Even for 20 minute time trial (time attack). I'm too cheap to use them as I run used full slicks. Hoosiers slicks and now Avon which are faster than the Hoosiers slicks were.

 

Cameron

[jt1]

General concensus around here is the A6's are a softer compound which heat up quicker than the R6's, have more overall grip, but then fall off quicker than the R6's. On a roughly two minute course, the A's are considered about 1/2 to 1 sec quicker than the R's, and the R's about 1 1/2 to 2 seconds quicker than the RA-1's. Wear and heat cycling are the opposite, so the A's wind up costing a good bit more. No surprise there, huh? Full race slicks are quicker yet, but even more expensive and good for only a few heat cycles.

 

jt

[johnc]

A6 for anything under 30 minutes. Even if they go off towards the end you'll built up such a lead...

 

FYI... the "latest" road race thinking is that its more important to get out in front on the first lap then to have a lot of tire at the end. The reasoning behind this is that you're less likely to be in any first lap wrecks and its much harder pass late in a race.

Edited November 16, 2009 by johnc

[260DET]

Thanks all for the advice, its just a pity that the RA1's are no longer available although apparently the new Toyo R888's have not been well received in the US so who knows?

[zclubhouse]

(Never ran in a time attack but heres my experience/witness.) I tried using a set of R6 for Autox which was a poor idea for individual run performance, but they did last me a good while. However a few friends ran an rx7 with the A6 compound in a time attack style format at BlackHawk and had nothing but good things to report. My best guess is that the A6 would offer you better performance in a hot lapping scenario than anything other than a full slick. You shouldn't have alot of trouble getting them up to temp on a shorter circuit as I have seen plenty of people were getting reasonable pyrometer readings after just an 1 minute parking lot thrashabout.

[wheelman]

So what are the opinions on Kumho V710s vs. Hoosier A6s?

[Mayolives]

So what are the opinions on Kumho V710s vs. Hoosier A6s?

 

I haven't used the A6 Hoosier but have used R6 (275-16)and Kumho V710 (265-16), both purchased new and for road course use. As stated above, the A6 have the reputation of not lasting through many heat cycles and are normally used for autocross applications. I get about the same lap times with either tire when new. After a few heat cycles, the Hoosiers may still look good but are really slick and lap times go up. The Kumho V710, on my car, will last longer, stay softer and faster, through more heat cycles that the Hoosier tire.

[johnc]

At the top levels of the sport (autocross and road racing) the Hoosier A6 is currently the faster tire. None of that applies to anyone here on this message board because our ham fisted driving masks the lap time difference.

 

The V710 is a better choice for us for the value reasons Tom lists above.

[260DET]

Yeh, realising your strengths and limitations is always useful on a race track which means that the hot Hoosiers are not for me So something that is consistent over a reasonable life span, Kumho seem to fill that requirement.

[wheelman]

Thanks for the replies regarding the A6 vs. V710 question.

I'm planning to run V710s next season but figured I'd ask just to get a feel for what you guys thought.

My primary reason for choosing the V710s is cost but based on what has been said they are more consistent for a longer period of time although initially a bit slower than the Hoosiers. I don't think I could tell the difference though, I'm far from a "high level" driver.

[Mayolives]

QUOTE: None of that applies to anyone here on this message board because our ham fisted driving masks the lap time difference.

 

Johnc is correct again. Few of us will ever experience the true potential of what our cars are capable of doing on the track. My "ham fisted" driving is always in the way

[260DET]

Depending on the circuit, even sports street tyres like Dunlop Direzza Sport Z1, Kumho Exsta XS and so on may be adequate for some drivers, those who are not chasing top times but just want to have fun and go fast enough to get the juices pumping. Such tyres will usually squeal too when getting close to their limit, quite handy that.

[katman]

Me thinks the RX-7 that won the ARRC in ITS this year was on A6's. That's 20 laps at Road Atlanta. We tried them on our 2 time ARRC winning 240Z once (with extremely well dialed in shocks before the SCCA banned them, bastards, but I digress, point is it was a well sorted car so if any Z could run an A6 it would have been us) and weren't happy with the longevity or grip but it's been several years and proly a few compound iterations ago. At the time we tried them on a Z the Speedsource guys were running A6's for qualifying only, they still raced on the R6's. But it appears now they may go 30+ minutes on a road course. With R6 Hoosiers the break in is everything for longevity so I would imagine same thing for A6's. Run them 2 laps until they warm up and them put them in a dark place until the next weekend. Don't even think about running them the same weekend you break them in. Used to make a huge difference for us in tire wear and grip longevity. YMMV.