For Those Using the Toyo RA-1 Track Tire

[nsxtasy]

You may have noticed that the Toyo RA-1 is now sold with a UTQG treadwear rating of 100 on the sidewall. Before this year, it had a treadwear rating of 40.

I just sent their technical folks the following question:

"I noticed that this tire recently changed from a 40 treadwear rating to 100. Is this because the design and engineering of the tire actually changed, or is it still the exact same tire but you decided to change the treadwear rating after further testing?"

I received the following response:

"It is the exact same tire we just decided to change the tread wear rating after further testing and feedback from consumer track use."

Track on...

 

[nsxhk]

Ken,

Thnx for the info, that's good to hear. I'm considering a set of those in 205/40/17 and 275/35/18.

OTOH, do you know if the RA-1 give any warning at all before they break loose? I recently changed to a new yoko street tires and they don't give me much warning at all

Thnx

Henry.

 

[titaniumdave]

Henry,
A couple of thoughts, the stagger of a 205 front and 275 rear is not recommended. I have found don't like more than a 40 mm difference or my car does not turn in well, and the rear tires want to break loose when I finally get them to start sliding, much harder to rotate the car on the track. I have run 215 and 255 and like that set up for road and track.

I am running 235 and 275 RA-1's on the track now, which I love, only have one day on them but I must say these are the best communicating tires I have run, once they are hot. They give constant feedback and very easy to make subtle adjustments and corrections. That said, I don't drive them on the street because I don't like the way they feel cold, I can see how folks spin their cars so easily on a cold set of race tires. I would not own these with out a set of dedicated track wheels.

 

[nsxtasy]

the stagger of a 205 front and 275 rear is not recommended. I have found don't like more than a 40 mm difference or my car does not turn in well, and the rear tires want to break loose when I finally get them to start sliding, much harder to rotate the car on the track. I have run 215 and 255 and like that set up for road and track.

I agree. Unfortunately, those widths aren't available in 17"/18". If I had to use 17"/18" wheels with the RA-1, I would probably choose Henry's 205/40-17 front size, and a rear size of 245/40-18. That would avoid all the fender rubbing of the next bigger 17" size, the oversized 235/40-17, which is not only much wider than stock, but also much bigger in outer diameter.

However, for my '91, I'm very happy using the stock tire sizes on stock 15"/16" wheels. They grip and handle very well. And they have the added advantage that I can fit all four track tires inside the car and drive to the track on my street tires. (As well as the fact that you can pick up a set of used stock 15"/16" wheels for next to nothing.)

I don't drive them on the street because I don't like the way they feel cold, I can see how folks spin their cars so easily on a cold set of race tires. I would not own these with out a set of dedicated track wheels.

When you talk about using them cold, I'm not sure if you're referring to street use, or track use. Most track tires need to be warmed up to really grip well, so it's no surprise that the RA-1 needs a full hot lap before they start really feeling good. But for "light street use", such as driving between the track and the hotel overnight, I think the RA-1 is fine. All of which is pretty much the same as for any other track tire (R compound).

I wouldn't own ANY track tires without a set of dedicated track wheels (unless your car is a dedicated, track-only car). Track tires wear quicker than street tires, and they don't do well on wet pavement, qualities that make them unsuitable for everyday use. (Granted, the RA-1 may be better than other track tires in both these respects, but not as good as almost all street tires.)

 

[Chris F]

OTOH, do you know if the RA-1 give any warning at all before they break loose? I recently changed to a new yoko street tires and they don't give me much warning at all

I have found that they will squeal before they get to their limit, when nice and warmed up. They still have decent adhesion past their ideal slip angle, and the ideal slip angle is larger than other R compounds.

In these ways, they seem to me to be more like sticky street tires than other R compounds, a bit forgiving.

On the other hand, when cold, the rears have jumped out from under me without making a sound. I run pretty low cold pressures though, and I was considering putting a couple more pounds in the rear. When I say cold, I mean second lap in the morning at an ambient temp of 40-45.
(Different car, your mileage may vary.)

 

[2slow2speed]

Ken,

Thnx for the info, that's good to hear. I'm considering a set of those in 205/40/17 and 275/35/18.

OTOH, do you know if the RA-1 give any warning at all before they break loose? I recently changed to a new yoko street tires and they don't give me much warning at all

Thnx

Henry.

Henry,

For what is worth, I run the setup that you are asking about and I don't have any ill handling characteristics on the car at the track besides some mild understeer on some of the slower section of the track, it still handles better than with my street setup of 215/40/17 and 275/35/18 S03's (about 2-3 seconds faster with the RA1's that was with the Tein's 10/10, have not had a chance to run the Type-R suspension with the RA1's yet.)

Andrie drove my car with the 205/40/17 and the only comment that he had was that I needed to have more negative camber up front. (used to run about -ve 1 degree now I am up to -ve 1.5 degrees)

Would have considered going with the 235/40/17's but it's too wide for a 7.5 inch wide rim.

Just my 2 cents.

Ken

 

[NSXDreamer2]

6 seconds gain from TeinRA, Toyo RA-1, Replica nsxR wing and Recaro Seat. First Track day of the year.
Last year Best time achieved at 85-90 degree, Kumho MX, stock suspension.

I credit the majority of gain to RA1, TeinRA had not been dialed intentionally, body roll is on par with Stock suspension...

Yes, tons of warning before it gives up traction, I had back off a little to just get the tire squeal. Haven't experience any "losing" grip situation yet... (Again, my first day of the year, not 100% trusting all my new modifications...etc.)

Also had a chance to drive to Track on Highway in huge down pouring and going over water puddle... Feels like the tires are good for even everyday driving. (if you can afford it.) Tons and tons of traction even it's cold.

 

[nsxtasy]

Also had a chance to drive to Track on Highway in huge down pouring and going over water puddle... Feels like the tires are good for even everyday driving. (if you can afford it.) Tons and tons of traction even it's cold.

Just be careful when the tires wear. When the RA-1 is new, it has lateral tread grooves as well as circumferential grooves, and the lateral grooves do a nice job of shedding water in the rain. As the tire wears down, the lateral tread grooves wear out first, while the circumferential grooves are still deep (i.e. before the treadwear indicator bars are flat across). At that point, the tread looks a lot like the Hoosier R3S04, with its two circumferential grooves. I can only guess that they won't be as good in the rain from that point on.

 

[NSXDreamer2]

(i.e. before the treadwear indicator bars are flat across).

wait a minute, Ken, does RA1 had "indicator bars"?? I thought they use a hole or dimple as indicators, no? :biggrin: http://www.toyo.com/tires/tire_lines/sports_car/ra1.html

 

[nsxtasy]

wait a minute, Ken, does RA1 had "indicator bars"?? I thought they use a hole or dimple as indicators, no?

It has holes/dimples in the outer shoulder of the tread, consisting of an outer dimple representing 2/32" with an inner dimple representing full tread depth. It also has the treadwear indicator bars going across all four of the deep circumferential tread grooves (not the center, shallower circumferential tread groove). They may not be visible in the photo, but they are on the actual tires. (I just went out to my garage to verify.)

 

[NSXDreamer2]

(I just went out to my garage to verify.)

hmmm, no work on Monday huh, Ken...

One more thing for me to envy you... :biggrin:

 

[nsxhk]

Thnx for the comment guys, greatly appreciated!

I think I'll give the toyos a shot

Henry.

 

[NSXLuvr]

So you guys don't recommend using RA-1 as your only set of tires?

I have S03's on right now. I want to step up to RA-1's next. Unfortunately, I do not have a way to bring a extra set of rims/tires with me to the track. So I am debating putting them on my only set of rims. I have to drive 150 miles to get to tracks.

Any comments?

 

[Andrie Hartanto]

No problem. first year I race in Honda Challenge, I drove to and from the track with RA1.

 

[nsxtasy]

So you guys don't recommend using RA-1 as your only set of tires?

I have S03's on right now. I want to step up to RA-1's next. Unfortunately, I do not have a way to bring a extra set of rims/tires with me to the track. So I am debating putting them on my only set of rims. I have to drive 150 miles to get to tracks.

Any comments?

If you're talking about general street use - leaving them on the car for months at a time while you're driving to work, running errands, driving on the highway, etc. - I think they are not a great choice, mostly because they wear faster than street tires, and they don't grip in rain as well as street tires. But if you're talking about driving 150 miles each way to and from the track, they should be fine (just like driving between the hotel and the track).

Incidentally, if your car is a '91-96 and you have the stock brake calipers, you can pick up a set of '91-93 stock wheels for ~$100-200, put the '91-93 stock size RA-1 on them, and fit the track tires/wheels inside the NSX, along with all your track gear. Like this:

 

[AU_NSX]

Incidentally, if your car is a '91-96 and you have the stock brake calipers, you can pick up a set of '91-93 stock wheels for ~$100-200, put the '91-93 stock size RA-1 on them, and fit the track tires/wheels inside the NSX, along with all your track gear. Like this:

Okay Ken.... Where is the after photo with you in the car as well....? :biggrin: I would really like to see that!!!

I agree with you on the stock 91-93 rims as well!

But my dilemma is now I have the Comptech BBK... 17's on the front is the smallest rim size I can fit now so I basically have a choice of:
Front: 205/40 17 or 235/40 17 these are the available sizes for track tyres in Australia (I cannot get the Japan only 215/40 17 Bridgestone RE55S's)

The 205/40 17 I believe is too small to run with 265/35 18 rear and the 235/40 17 will rub if I don't take out the wheel liners... In addition, if I do run the 235/40 17 up front I reckon I would have to increase the rear to 285/30 18 which is too low a profile for a decent track tyre...

What to do? ?

 

[Andrie Hartanto]

285/30 18 which is too low a profile for a decent track tyre...

What do you mean by this? The less sidewall you have almost always the better. You can tune the suspension better as you are eliminating more variables.

 

[BioBanker]

What R compounds are available for someone wanting to turn their stock 02+ rims into track wheels?

Stock set up is:
Front - 215/40/17 on a 7.5inch +55
Rear -255/40/17 on a 9.0 inch +56

Im shooting blanks from everyone on the fronts. Surely there is something?

 

[2slow2speed]

What R compounds are available for someone wanting to turn their stock 02+ rims into track wheels?

Stock set up is:
Front - 215/40/17 on a 7.5inch +55
Rear -255/40/17 on a 9.0 inch +56

Im shooting blanks from everyone on the fronts. Surely there is something?

You can always use 205/40/17 with a 7.5 inch wide rim, that's what I use on my car, and you can go with 255/40/17 in the rear on the RA1's.

For the most part that should work ok.

Just my 2 cents.

Ken

 

[Ponyboy]

What do you mean by this? The less sidewall you have almost always the better. You can tune the suspension better as you are eliminating more variables.

Uhhh, yeah. I use 285/30-18 with no handling or grip detriment and with good feedback on what the rear is doing.

Help?

 

[nsxtasy]

You can always use 205/40/17 with a 7.5 inch wide rim, that's what I use on my car, and you can go with 255/40/17 in the rear on the RA1's.

For the most part that should work ok.

That's what I would suggest, too...

 

[titaniumdave]

But my dilemma is now I have the Comptech BBK... 17's on the front is the smallest rim size I can fit now so I basically have a choice of:
Front: 205/40 17 or 235/40 17 these are the available sizes for track tyres in Australia (I cannot get the Japan only 215/40 17 Bridgestone RE55S's)

The 205/40 17 I believe is too small to run with 265/35 18 rear and the 235/40 17 will rub if I don't take out the wheel liners... In addition, if I do run the 235/40 17 up front I reckon I would have to increase the rear to 285/30 18 which is too low a profile for a decent track tyre...

What to do? ?

I run 235-40-17 on 8.5" wheels, they don't rub on the car, only on the non-compliant clamps at full lock. I like the balance of these with 275-35-18 on 10" wheels on the rear, I would not want more rubber than that on the back end, use a softer sway bar if you want more traction, I am going back to my stock bar on the back for that reason.

 

[nsxtasy]

The 205/40 17 I believe is too small to run with 265/35 18 rear

Not true. That combination will work just fine.

I run 235-40-17 on 8.5" wheels, they don't rub on the car

Most folks I know who use that front size have found that rubbing is a significant problem. Some are willing to live with it, and others have removed the fender well liners (and are thus willing to risk "reverse dings" from gravel).

 

[Ponyboy]

Most folks I know who use that front size have found that rubbing is a significant problem. Some are willing to live with it, and others have removed the fender well liners (and are thus willing to risk "reverse dings" from gravel).

Count me in (unless nsxtasy is already talking about me). Rubbing was an issue...until I took out the fender lining and took a BUFF hammer to the fender wheels. I put in some black foam liner from a spray can to allieviate the "reverse ding" effect.

 

[NSXDreamer2]

Count me in (unless nsxtasy is already talking about me). Rubbing was an issue...until I took out the fender lining and took a BUFF hammer to the fender wheels. I put in some black foam liner from a spray can to allieviate the "reverse ding" effect.

hmmm, that's interesting, I would like to know more if this is the acceptable option for the missing fender liners...