Not sure if this is the correct forum for this but I wanted input from those who take their cars at the track.

I am at a crossroads so to speak. After 3 yrs and 8 driving schools, my BF Goodrich KWDs are quite worn and not going back to the track. I have them mounted on 17in ASA AR1s. I can also feel that I've reached the grip limit of these tires.

My first issue is to go to R-comps or not. I've had diverging opinions on this but am leaning towards them as I feel they would stand up better to the track. I think I have enough experience with the car to be able to safely explore their limits.

My second issue is with wheel and tire size combos. People are using 15s, 16 and 17in wheels with various witdth/profile. To be honest, I'm quite lost with all of this and would appreciate some input.

 

ok. since nobody else wants to reply, i will....don't worry.

i say go w/ the r-comps. when i destroyed a good set of street tires in one weekend, i vowed to never go back on track w/out r-comps. you will like it and there is no going back.

i have heard, too many times, that r-comps will "hide mistakes and slow driver development". i call BS. how can a tire that breaks loose more abrubtly and w/ less (audible) warning, cover a mistake? they just have more grip. a lot more grip. you will be able to go faster. just take the level up in baby steps until you find the limits of your new tires.

as far as size.....there are two considerations. 1. brake clearance. will a 15/16 inch wheel clear your brakes? in your current state, i would say they probably will. 2. weight. a 15" wheel will probably weigh less that a comparably priced 17" wheel. lighter is way better. when i put on my light-weight 17's, it feels as if my suspension is completely different than my relatively light 18" street wheels.

RSR and JPropane both run 15's. onasled went w/ 17's to clear his BBK.

the other thing to consider is the availablity of r-comps in the correct size range. there is a better selection of 15 and 17 inch r-comps than there is in the 16" size. i have a buddy who runs 16's and makes it work, however. he runs V710's, not sure of the size. they look like big doughnuts compared w/ my 225/40/17 hoosiers. i am switching to even wider tires on my race build.

look at a wheel/tire combination before buying wheels. i have several sets of racing wheels for sale because i bought them before i decided to build a wide-body race car.

buy the lightest wheels that you can afford. it really has a dramatic effect on the handling.

greg

 

Except for the first paragraph, which I disagree with, the rest is sage advice. With regard to R-comps, they do brake loose with less noise--it's a somewhat dangerous setup if you're new to the track. You learn to listen to the street tires, then feel what they're doing, then you can take that "feel" over to the relatively quieter R-comps. Also, R-comps allow you to cheat--they have comparatively so much more grip, I know I can be slightly off line and still pull the car over to the apex, much more forgiving--but not the quickest way around the track. You can't do that with street tires; they force you to learn the line correctly. On a new track, I'll run street tires until I get a feel for it, then switch to R-comps...

But that doesn't apply to the original poster--looks like he's ready for R-comps, and like Greg said, once you go from street tires to R-comps there's no going back.

The one other advantage of 15's is they make the gears shorter (if you run a smaller diameter 15, I run a 225/45/15), which comes in handy on my 2006 R53. I'm not sure about the gear ratios on the R56, but if they're similar to the late model R53, the smaller diameter tire really helps. It's even a bigger help for the early model R53's, which even had taller gears.

Anyway, like Greg said, your brake kit may be the limiting factor--so start there, see what sizes clear (if you have 12.2 diameter rotors for example, 15's are out), then pick your tire, then your rim.

As for 15/16/17, I prefer 15's for the above reasons. Others prefer 17's--they do offer a little better turn in, and lightweight 17 rims are available, but very expensive; 17 inch tires are significantly more expensive too. It's a personal preference thing, I've driven both and won't run anything but a 15 on the track; others swear by 17's, and there are plenty of quick dudes running that combo as well.

Like Greg said, the choices in 16 is relatively limited, and seems to get smaller every year. 15's will always be available because of the huge Miata crowd, and 17's fit so many different applications they're even more available than 15's....

 

Thanks for the advice. So far, the people with track experience are saying the same thing you are WRT R-comps. I think this is the way I will be heading. Somewhat more expensive but they will end up lasting much longer no doubt while providing more grip. I don't want to break track records by any means but driving a 'momentum' car rather than HP car, it is important to keep the speed in the twisties.

As for the wheels, I will do more research for sure, but I do feel sorry now that I bought those ASAs. Good wheels mind you but they weigh a ton I can always sell them so not all is lost. The guys recommending the 15's like the fact that the smaller wheels give them more effective torque, although you end up shifting alot more...

 

Thanks for the advice cct1. That's what the Chief Instructor at the school last week indicated when discussing R-comps. Most of them will give way progressively but no audible warning like a street tire. Only the butt-o-meter works

I have the standard brakes on my R56 which is the same as the R53 JCW I understand. The local guy recommending 15's has a set so maybe I'll go over and do a test fit. Don't think I'll be going to BBK now that the Carbotech pads are working for me. What wheel brand are you running ? slinger688 is running Rota.

 

I'll try and give a little advice. Please take it for just that. I'd suggest you stick with street tires. Two reasons. They are cheaper and they offer a little more feedback via noise. I would suggest you have a set of dedicated track wheels and tires that are not for daily driving but no need to get out of hand with the cost. I'd also recommend buying someone elses old wheels. To often you see people buy hot new wheels for the track and you will see them look terrible after one weekend of heavy track use. I'm a big fan of Carbotec brakes but if you get your brake dust covered wheels wet they will eat away at your wheels. The other big reason for "sticking" to non-r-comp tires is that if you're just doing DE's there is no check to be had at the end of the day from your first place HPDE finish. I fell into the same boat you're looking at now when i was new to it. I do have 4 sets of tires and wheels for my MINI. 3 sets are r-compound. That's a lot of money maybe i shouldn't have spent. I thought i needed it them. To a degree I did. Instructing pays my bills. You will get a lot more respect for seasoned drivers when you pass them on street tires. It also makes packing for the track much easier.

 

As an Instructor at DE and Autocross for over 20 years it does sound like you are ready for the R Comps, as another poster pointed out I would disagree that R comps dont hide Mistakes they do in my opinion hide many. Learn how to drive a slow car fast on any track no matter what the setup, and you will gain alot of respect.
Street tires will long out live your R comps, even if you only use the R comps for a season they are going to dry out, crack and get hard if you do a few events on them. Plan on buying a set every year as most do.

 

i am pretty much stuck in my position and i will try to justify it. a good set of performance street tires is not much cheaper than a set of r-comps (maybe $200/set). when i found that i could destroy a set of street tires in one day, it became clear to me that r-comps were the only option. the audible clues to adhesion limits are justified, but overcome by experience. i think that the OP has a sufficient butt to feel car rotation. i used to get 4 weekends from a set of r-comps (with dimished performance at the end), but who cares. as you said, there is no money for finishing first in DE. better than one weekend on street tires.

i agree w/ your statement that one should buy someone else old wheels....i have four sets for sale in the marketplace! shameless plug.

we have followed a similar path, but have different advice to those who follow. hopefully, the differing opinions will cause the OP to evaluate and make an educated decision.

greg

 

Roca: i don't want to be a confrontational A$$, but i will have to give you a friendly challenge. how do R-comps hide mistakes? r-comps have higher grip limits, but a mistake is a mistake. if one over-rotates a car, it doesn't matter if it is on street tires or r-comps. i don't advocate a novice starting out on r-comps, but the "cost" and "hides mistakes" arguements don't hold water for me with an experience DE'er.

greg

 

just two bits on the R compound discussion

max grip on my STX Cooper with DOT 140 treadwear is 1.15 g

max grip on the same chassis and surface with AS304 was 1.22 g

the sticky street tires are getting pretty close - within about 5 percent

recommend 15" rims by the way, as a wheel tire combo at 24" diameter is worth around 7 WHP compared with a 25" setup (e.g. 16s or 17s) on a strong Cooper S.

About 4% more thrust at the contact patch.

The same advantage is conferred on the brake system too.

Cheers,

Charlie

 

Good points. The used wheels would certainly be a good option for the reasons stated and to keep costs down. Passing everybody on the track is not my goal ! If I'm running mid-pack I'm happy. My main reason for wanting to switch is the higher grip of course (good for momentum car like the Mini) but also a little more longevity.

I see you instructed at Tarheel Chapter. JoElla John was my very first instructor at Mosport International 2 years ago. I had a great time. I even had the privilege to ride with her husband Richard, who unfortunatelly passed away a few months later.

 

Charlie, Those are interesting stats. My current track tires have a treadwear of 300, so certainly not the best I can get from street tires. Something to consider for sure. I like your numbers on wheel diameter effect.

 

A little late to this discussion, but wanted to clear something up. A good set of high performance street tires will outlast R-comps by a long shot.

I could see snow or maybe all season tires being trashed in one event, but unless you are way over driving the car, there is no way you are going through a set of new high perf street tires in your typical HPDE environment.

I run Hankook R-S2 street tires on my 911 track car, and they last about 4 times as long as my R-comps do, and I'm pretty hard on tires. Believe it or not, but max performance street tires really aren't that much slower than an R-Comp like MPSC, R888, NT01, etc. Obviously a set of Hoosiers will crush any street tire.

I actually like driving on street tires better than R-Comps. It forces me to learn how to keep up with the other instructors who are on R-comps. I usually find if I start out on street tires the first day, and then go to R-comps on the 2nd day, I'm significantly faster than if I was on R-comps the whole time.

-Scott

 

http://www.youtube.com/user/l8apxr#p/a/u/1/dA7ln8FJoLA


Here's me from last month at VIR full with a 2:21ish lap. I've got another session on youtube also from last week with lots of traffic. not idea what kind of times. that's when my clutch gave up.

 

I just sold my 16 to get a 15, Im on rt615 now and love them,but I just had a ride in a mini runing nto1 tires and will be trying them next. I am really glad I went down to a 15 inch wheel it really helped my gearing (2002 r53). Plus the weight difference.

 

I have done a ton of DE’s, 10 or more a year, and I’m a DE instructor so here’s my 2cents on R-comps.

Hide mistakes? Not necessarily. Get an inexperienced driver in trouble? Yes. If your skill and experience isn’t up to the extra speed you can get with the R-comps, you could get yourself into a situation you won’t like.

Extra grip = extra speed = need more brakes. Don’t forget this one!

Extra grip = extra speed = need suspension mods next.

Break away without warning? It depends on the tire. I run Nitto NT01s and they are quite vocal long before you are in trouble.

Cost more? Wear Faster? Yes. I go through three sets a year on average.
Size? I don’t have any choices. I have 13” front rotors and have to run 17s to clear them so I run 215/45/17s.

After 8 DEs you should be ready for R-comps just add the speed gradually over the first session or two and get accustomed to the new grip levels.

 

Well, for hiding mistakes, I've been slightly off line, or at the wrong speed, and still been able to get back to the apex on R-comps, a move I'd never be able to accomplish with street tires. So maybe hiding a mistake isn't the correct semantics--but obviously it's better/faster to be on the correct line all the way, and IMHO it's easier to learn the line on street tires first--they force you to take it a little slower; they aren't as forgiving.

Amen to the extra grip points.

I run the Nitto 01's too, and while they do give off noise, it's nothing comparable to the howl street tires give. I couldn't imagine driving on Hoosier's....

Having seat time on street tires IMHO has kept me from doing anything too stupid on R-comps. Our BMWCCA chapter won't allow R-comps on the beginning run groups.

 

I don't see front camber plates listed in mlg2ca mods. They would help either type of tire last longer and work better.

 

Wooah! Need to change the camera angle! Can't see anything(except you - lol), darn it....

 

If you are going to have second set of wheels, then do yourself a favor and get some 15X7, 15X7.5 or 15X8 inch wheels that will fit over your brakes and wrap them in the beautiful sticky goodness of 205/50 or 225/45 R comp tires (Toyo 888, RA1, NT01) and don't look back.

R comp tires are not some fabulous mystery only to be divined to a special few with enchanted driving powers. Use them, enjoy them and have a blast.

Mio

 

I'll second that ^^^

I run 15 x 7.5's wrapped with R6's......225/45's. Love them. A bit pricey at $218/ea tho.....

This season for the first event(s) I'll be trying NT01's to see how they compare, wear-wise and lap time wise. Cheaper as well at $140/ea.

 

Just an FYI, onlinetires.com has the NT01's for $114 for the 225 and $108 for the 205's. I've got a set of 888's to start the year but will try the NT01's later.

Mio

 

Wow! I wish I didn't have to wait 3 1/2 weeks to see if I like the Nt01's or else I jump on that deal! I bet the sale will be done by then...

Thanks for the link..

 

I think I will be be the market for some soon.

 

Just checked out their site. They want $129 for the NT01 in 215/45 17 size but shipping is quite high from CA.