Race Tires Surveys - what's your take on this?

[offcamber09]

I only have 4 laps on the R1s (I was really hoping for a dry TT last event)- but it is clearly faster than a v710. The R1s was about 1.5 seconds quicker than the Toyo RR in my car chic/chic. The R1s is cheaper, in my size, than the v710 at Tire Rack- but clearly won't last as long.
On a sidenote- the Toyo RR is actually wider than the R1s when stacked up, mounted and inflated.

[PaddyMcP]

I would say that a fresh R6 has about 1 to 1.5 seconds on the NT-01 at NHMS, but it isn't always achievable unless the conditions are ideal. The NT-01 is such a versatile tire in that it works in a very wide temperature range and seems to be happy with large slip angles, they are really easy to drive on at the limit. I wear them down to the cords and they don't appear to fall off at all.

I agree 100% with that, and take it a step further to say that not only do the conditions have to be 'right' and the Hoosier have to be fresh, but so does car setup.

How many of us have done real data logging and tire testing?

When I say that 'some people' say the NT-01's are every bit as fast as the Hoosiers, I'm talking about guys that run cars with crews, test and keep records with pyrometers, and make alignment changes at the track. These are guys/builders that have track-specific suspension setups (spring rates, shock & sway adjustments) as well as track-specific setups (alignment, ride height, corner balance).

In my personal experience, the Hoosiers are a hair faster given the right conditions. The tires have to be new and the track conditions have to be cool, and it has to be the 'right' track. The July NHMS event was hot, the A6's were too greasy, the R6's OK, but the Nittos would have been the better choice. I've been experimenting a bit with Nitto tire pressure, but think my setup would need more camber to effectively run the Nittos. Though I own and occasionally use a tire pyrometer, and setup the car a couple of times a year, I can't say that I've ever optimized any setup specific to the tires I run.

I would love to know the pro team telling you NT01's are on pace with the R6.

[savage217]

I can confirm what Chris was saying in regards to the width of the v710. They absolutely run narrow compared to other tires. Compared to my BFG's they are substantially narrower. On the same wheel, I could not stack a set of them without the rims touching each other. with the BFG's the tires protrude further out and more square sidewalls to the point where I can stack a set without any wheel touching at all. I will say the Hankook C51's seem to run about as narrow as the v710 IIRC.

[Mick]

I can confirm what Chris was saying in regards to the width of the v710. They absolutely run narrow compared to other tires. Compared to my BFG's they are substantially narrower. On the same wheel, I could not stack a set of them without the rims touching each other. with the BFG's the tires protrude further out and more square sidewalls to the point where I can stack a set without any wheel touching at all. I will say the Hankook C51's seem to run about as narrow as the v710 IIRC.

It must differ depending on the size you get. My 225/50/15 V710's have been wider than any other tire I run, except the Hoosier which they are on par with.

[6PAK72]

Couple things:

Grassroots Motorsports did a very nice side-by-side last month on 5 tires, including the R1R. Check it out.

Next, at WGI this weekend the track was very, very hot - 101 air temp and ??? more on the asphalt. The RA'1's on the Miata were solid, and had the same slip angle acceptance I'm used to feeling. My times were within reason of my "cool track" times.

Tuesday I swapped to SM6, and through 6 sessions (yes, 6) did some very thorough testing of tire temps/pressure and driving style. I used a pyrometer to work out hot temps and pressure, and came away with a slightly higher temp setting than I had been running. Once there, the SM6 gave a feeling of smoothness on turn-in that the RA1 don't have. Also, the SM6 has dramatically better linear grip - my braking zones could be moved 50 feet. It's more difficult to control rotation in a trail brake, but that may be my skill level. And I perceive that the SM6 allows me to turn in slightly tighter and truly nail an apex.

After 10 laps, the SM6 definitely was "slippery" on the turn-in, and they seemed closer in feel to the RA1.

I data-logged all weekend. As for driving, I went out and drove COM-style TT driving speeds on several laps each session. Times were in the 2:20-2:21 range. I then did 9 laps at 85% - not hammering on the throttle exiting turns, slower turn-ins, just really working on nailing the line and being hyper smooth. The outcome was 1 second slower.

The data overlay on the RA1 is fascinating. You can clearly see the braking zone difference, you can clearly see the tenth of a second gain post-apex over the RA1.

SM6: It's just Faster. (for me, on a Miata, set up the way mine is, on a hot track at Watkins)

[CP]

I'll add my $.02. Three years ago I raced a shaved RA1 and full tread NT01, last year the SM6 and this year the ToyoRR. Most driving is at 97%. I don't have a huge budget so I use my tires until they begin to get slow (like 2 seconds off the pace of the leaders), unlike some guys who run new tires every race weekend. I initially heat cycle all my tires and let them sit for at least a week. I also flip tires on wheels between race weekends, as I have an old Coats machine and bubble balancer at home.

Shaved Toyo RA1: Sloppy with a 4/32 shave at turn-in. They can handle extreme slip angles without getting overly hot and greasy. They get more precise as they wear (less tread depth) but I found that I was ditching the tires before cords could be seen because they'd turn blue on the edges and get hard. Toasted. I found that a 3/32nd shave worked best for me, a good marriage of tread life versus heat cycling.

NT01: Tread is too deep at 6/32 new. There's a very pronounced delay at turn-in while the tread squirms and then the tire bites. It was very disconcerting at Lime Rock in particular, turning the wheel at the end of No Name and then waiting for something to happen. This tire has a strangely deep growl at the limit that takes some getting used to. The wear was good but they slowed down a lot near the end of life. It takes a lot of heat cycles to cord a 6/32 tire, so they were mostly cooked by then. Turn-in response did get a lot better as they wore due to less tread squirm.

Hoosier SM6: Much stiffer sidewall than the RA1 so turn-in is much more crisp. When new, braking points can be moved 50ft closer to the corner (like T3 at NHMS). These tires need to be driven much more cleanly than an RA1. If a driver abuses them and slides them frequently, they begin to go away halfway through a race. My strategy last season was to drive clean and wait out the cars in front of me and they always came back to me halfway through a race. This tire has great grip when brand new (after a proper initial heat cycle) but their durability sucks. Mine would begin to slow down after 6-8 sessions and I can't afford that.

ToyoRR: I really like this tire after one race weekend (2 quals, 6 races). It's got the turn-in response of the Hoosier but can be driven at RA1 slip angles without getting too sloppy. They take about the same 70+psi to seat the bead as the Hoosiers, so the sidewall is stiff. Grip when new is very similar to the SM6, as I could get into NASCAR a lot faster than expected and pick up the throttle sooner than with a shaved RA1. Braking is about the same as the Hoosier, however breakaway is slightly softer in a corner. I haven't run them enough to note wear characteristics but I'm expecting (hoping) similar durability to the RA1. At our next practice day, I'm going to begin dialing in pressures based upon tire temps.

In summary, the SM6 is the fastest out of the box but needs to be taken care of or it gets slippy. Plus they heat cycle out very quickly. If you've got the budget, run these. For me, I think the ToyoRR is the tire I'll be using for the next few seasons if permitted to do so. It's got the best balance of price, grip, steering response and hopefully durability.

[TroyV]

Definitely true about the weird growl with the NT's, CY. At first I thought I had cooked a front hub. The noise was similar.

[dtlemoine]

Definitely true about the weird growl with the NT's, CY. At first I thought I had cooked a front hub. The noise was similar.

+1

Freaked me out a bit at LCMT - thought I might have to suck up to someone to stash my daily driver on a trailer for a ride back home as I didn't bring any spare hubs/bearings.

[chaos4NH]

You guys know me..used tires. I ran 14 practice laps at, very slow it seems (best 1:25.008), then the 3 time trials laps, somehow in the 1:21- 1:22 range. Point is I was running used (1 from David L and 3 from Chad) NT01s. I was very pleased with them. How is that for non-scientific opinion? I guess a few more laps (never been to Lightning before) and I might have been able to truly "test" the tires.

[6PAK72]

Great input, Cy, thanks.

As always, a font of wisdom!

[Dtangard]

Has anyone experienced the Toyo RR tread splice spliting issue?

[jeffw]

Has anyone experienced the Toyo RR tread splice spliting issue?

I haven't. I've got a set that's almost done. I mounted them per the specs, and then flipped them part way thru and continued to follow their mounting specs.

[CP]

Same here. I expect my current set to be cooked after the next race weekend at NHMS and will monitor the tires throughout the event. I think only a small batch of tires was suspect from a single production run, not every RR ever made.

[Dtangard]

Thanks for the response on the RRs. I'm still torn on what to get for my next practice set. I'm thinking either the z214, nto1 (current tire), or RR.