I'd love to hear from SleepR1 on this (since it was his advice that lead me to my current wheel setup). Based on his research I went with 8.5/9.5 BBS RG-Rs (17s). I've been getting track time and now have moved to HPDE 3 and it's time to ditch the Toyo T-1s for a R compound, and I've chosen the NT01 Nittos vs. the Toyo R888s based on what I'm hearing at the track. The difference is that they don't produce the NTO1 in the same size for the rear. The Toyo T series is 265/40ZR17 while the closest on the Nitto is 275/40ZR17:

275
OD = 25.6"
Width = 10.9"

vs

265
OD = 25.3"
Width = 10.6"

So, I'd be going with another 3 tenths of an inch width in the back, which if you divided by 2 is .15" on each side. I think I've got the room, but it's tight - at the ride height I'm at now you cannot put a finger between the tire and lip.

Anyone anticipate any fitment issues? I use Ground Control Advanced Design coil-overs, so I can adjust ride height up a tad to compensate, and would also consider rolling my fenders in the back (I'll eventually get flares and an even bigger tire set up, but that's a ways down the road).

Advice appreciated. Am I worrying about nothing?

Beast

 

What is the offset of the rear wheels?

FYI these guys do a lot of race tires. I see them at SCCA events often. They are in Castro Valley.
http://www.rogerkrausracing.com/

 

snip from old thread:

As quoted above the only acceptable BBS RG-R fitment for Rx7 Type FD3S is 17 x 8.5, 37-mm offset part number RGR-722 for front; and 17 x 9.5, 38-mm offset part number RGR-726

End snip.

Here's the original thread:

https://www.rx7club.com/showthread.p...&highlight=BBS

 

That is pretty tight with that offset running at or below 25". I don't have any personal experience with those sizes so I'm of no further use here.

 

I will either have to raise the back up a bit or roll the lips on the rear....or both First thing to do is buy the tires and then mount them up and see how it looks.

 

Keep in mind the larger rolling diameter of the 275/40 will hurt you a bit vs your old 265/40. I've been running 275/40s out back for years and installed 4.3 final drive to help mitigate this problem.

you're running 255/40 up front?

 

Ah, Goodfellas, glad to have you chime in. I currently have the 'SleepR1' setup:

Wheel offset posted earlier above.


T1-S
F: 235/45Zr17 96Y
R: 265/40ZR17 97W

I had not noticed that the 275 specs for the RA-1 (I'm trying to find a set, it isn't easy) is 25.7 OD vs. 25.4 OD, so it's 3/10th taller. Now, I am running 400 at the wheels on a track only car - do you think the stock 4.1 gears will care?

We might as well also talk about the fronts, because the tire dealers are also having trouble sourcing the 235/45 in the RA-1, and might only have 235/40s. That would drop me from an OD of 25.4 to 24.4 ( a full inch, or half inch drop) and widen the front from 9.4 to 9.6 (a tenth on each side). I already had to do a modified roll of my front fender to support the 235/45 - going wider isn't going to help, but if it's a half inch shorter that can compensate, yes? Also, I run AD coilovers so I can adjust ride height.

What is the best thing for me to do given that I've exceeded the limits of the Toyo t1-S? I'm rethinking my decision to go with Nitto NT01s due to a conversation with Mike Lock who said the RA1 has better manners and resistance to heat cycling...if I can't get RA1s he recommends the BFGR1, which is a 40 treadwear vs. the 100 of the RA1!

I'm stuck in tire hell, help me get out.

Beast

 

The limits of the T1S are easy to exceed. I did in my 189 crank HP BMW. Since you've had those for 4-5 years, the rubber is probably dried out and even less grippy than they ever were.

For a track only car, its great to have a nice grippy tire that can last through many heat cycles, stays consistent through your time out on track and is communicative. Since I'm not blessed with Lewis Hamilton, Senna or Schumacher's driving skills, I prefer a tire that is more communicative first, offers good grip second, stays consistent for 20-30 minute segments, wears OK and is cost effective. The Toyo RA-1 is an excellent tire in all those respects. Slightly less grippy options but more streetable options include the Bridgestone RE11 and the Dunlop Star Spec (which I run). There are others too. B/c its easier to drive at the limit, you can learn more from these types of tires too than you can from a slick.

Most slick like tires don't provide as much communication. They'll grip like crazy up to a point and then they break free. If your skills are at that level, its all good. Ptrhahn runs some slick tires and so does Fritz if you want to do some research into some of their old posts.

 

Everything you say jibes with other input from more experienced racers. I still have a ways to go and definitely need a tire that doesnt' go to the edge of grip and then just cut loose, which is why the RA-1 seems like the right next step for me. The question is - can I get them? I have two dealers seeing if there are any 235/40's or 45s and 275/40s out there. Actually, I found one dealer who has the 235/40s, just doesn't have the 275s.

If the RA-1 is out, then I'm likely looking at the R888, NT01, or BFGR1 (one notch above a slick). I do not wish to use a streetable tire because...it doesn't see the street anymore. I'm not hearing really good things about the R888 (people either have not yet figured that tire out, or it just plain isn't as good as the RA-1), and I hear the NT01 doesn't have good durability. Mike Lock raves about the BRGR1, but also says it isn't as durable as the RA-1 and given where I'm at (just moved to HPDE 3), he thinks I don't need a faster tire, just a better one to learn/move to the next level.

I guess I could also look at the Hoosier A6. Not sure what sizes they have.

 

i've heard this too. two data points.

1. the r888's last longer. we can run the rear tires on the honda for 25 hours and still have meat left. in the front they probably go 10-12. this is all at once. if you run sprints they last longer. we bought 16 for the 2008 25 hours of thunderhill, and have worn out 1 tire. 1! you can't do that with the ra1's

2. except mr lock, the other complainers are slooooooooow.

also we timed a couple of laps in your group, and tire selection at that speed shouldn't matter. although if you're gearing up to a race program it might be good to start collecting tire temp data, and tuning the chassis on a current tire, as a different tire needs a slightly different setup.
this leaves out the Ra1 as its gonzo...

so if we traded places, i'd pick the tire that fits, even if its a little smaller, and work on the driving.

 

Last weekend, we were monitoring tire temps and had things pretty even on the outisde, inside, and middle....so for what was left of the tires, the chassis setup was ok...just had zero grip. It's very exciting full power fourth gear and drifting through the apex of seven (the car behind me said I had the rear end stepped out 6 inches all the way through the turn). I hit 140mph by the start finish line. I just couldn't get any decent times because in group 1/2 you can only pass on the straights and the novices are...well, novices. I'm really supposed to be concentrating on line and track awareness at that point, but it is still nice to get some clear track and put together a nice lap. Problem was we were catching lap traffic on the first lap!

Agree with you that at this point, fitment is really best - since I only do 2 events a year, longevity really isn't an issue. I'll also take a look at the R888 fitment and make a decision next week. I'm also still waiting to hear back from the dealers to see if they manage to scrounge up a set of RAs that will fit my car. The RA just sounds like a good tire I want to try if at all possible.

I've always supported Toyo due to their support of NASA and the SpeedWorld Challenge, but if the R888 isn't cutting it, they need to hear it by people voting with their wallets. I'm glad to hear you're getting good use of it. Are you with Midnight? Thery'e are good dedicated group. I see them at every event I've been to at Thill.

 

roll and pull the fenders a little bit you will be amazed how much space you free up

 

yeah you need to move up.

ra1's were good, r888's are better, at least for us. mr tommy lo set a personal best latime in the car on leftover 25 hour r888's that weekend 2:06:3 in h4 trim (2480lbs/140hp no vtech)

yep still with midnight, and we are at every nasa event...

 

I understand the same from speaking with people at the track.


Beast - how come you are only doing 1-2 track days a year? If its that low, go with something like the Dunlop Star Spec. Price is right and they are great track tires and potentially a bit easier to drive than the 888.

 

I'm only doing 2 track events a year because of time and money. I have many interests (golf being one, I live across from my club) , and it's tough to do 'everything' and stay solvent (and married). I do try to make every outing a two day event so I can get solid time and back to back sessions to improve learning and retention.

Obviously there is a day of fender rolling in my future - need to wait until summer time so the metal can get nice and warm to faciliate. Now evaluating BFGs vs. R888 vs. NT01s since it looks like RA1s are nowhere to be found. Probably going to drop to 235/40s in the front and 275/40s in the back based on the sizes that are available in both.

It's nice to have these kinds of problems.

 

I have a source for RA1s I can set you up with, I'm currently running 255/40 and 275/40 and was very satisfied with their recent performance on the tail of the dragon

 

I've heard nothing back from Sierra Tire or AIM regarding getting Ra1s (matching set - Sierra has the backs but not the fronts, AIM was totally out.)

In looking at the specs compared to what I'm running now, the BFGs actually offer a closer fit than the R888s, but either one works. BFGs being 40 treadwear makes them even stickier, which is likely why Mike Lock likes them and also says they get faster laptimes.

I don't think I can do 255 on front - if you're running RA1s that's 10.4 inches wide up front vs. 9.4 inches on the T1-s 235/45, so that's a full half inch closer to the edges of my fenders. I'd need to run flares, and if/when I go to flares I'll got to a wider rim than 8.5.....probably go to a 9.5 or 10 inch then.

 

You have way too much power to worry about that!
In which gear do you stop spinning your tires, 4th?

 

You absolutely can run a 255/40-17 up front. It's a 25 inch rolling diameter and fits perfectly on an 8.5 inch wide rim. Also, you don't need fender flares to run 9.5 or 10 inches up front, it's all in the offset. Hell, you can run 10 inch wide up front with 285s as long as you have coilovers

Not with the RA1s, those suckers GRIP

 

How is the grip compared to R888's? I just found two R888's in 18" 265 trim for $390 brand new. Once tuned i'm hoping for 500whp, will this be sticky enough for a hard 3rd gear pull?

 

the r888's have A LOT of grip. They held up to a full season of trackday abuse on my friends 600awhp GTR. and he was only running 255's.

 

I pulled the trigger on the BFG R1s, 235/40 front, 275/40 back. We'll know how they fit in a couple of weeks. If it looks like I can get even wider once these are on, I'll consider 245 or 255 once I burn them up. Thanks for all the input.

Beast

 

I'm curious how the R1's work out for you - it's a new tire with some nice sizes for us!

 

I'll let you know end of June - will be at Infineon in HPDE 3 for 2 days, plan on driving the ***** off it. Got 3 of the 4 tires in, one has to come from a warehouse in the mid-West. Once they all come in I will have them mounted and filled with nitrogen. Plan on starting them at 32 psi cold and see how it goes, working up to 36 to 41 psi hot per the BFG site for a car of our weight.

http://www.bfgoodrichtires.com/asset...ne_2.26.07.pdf

 

The 275/40s on the back, coupled with the 'straight shoulder' of the BFG R1s, fills the wheel well right up to where the fender meets the fender lip - I definitely must roll the lip, and even after that might have a challenge that requires some pulling of the fender or slight raising of the coil-over ride height (don't want to bring the rear up, takes weight off the rear and the damn thing's already tail happy under a half tank of gas). Fortunately a friend has scored a fender rolling tool and I will roll this weekend and see how it looks for Infineon on the 27th and 28th.

I'm now thinking flares are not so far away - either JKL's more subtle ones or Pettit's "in your face" wide rears.....but that means I can go to 11's which means I'll need flares on the fronts......<sigh, it never ends>.

The saga continues....

Beast