dannyc

Hi all,

I went to my first track day in the RX-8 last Friday at Nelson Ledges, OH. The car is stock with BFG KDW tires. I've autocrossed with these tires several times and chose to aim for 41psi hot which is what I autocross with. It was HOT, HOT, HOT that day (90-95 degrees F) and we ran 30-minute sessions for six hours. I was pleased throughout the day since all four tires were building up pressure evenly to 41psi so I assumed they were heating up evenly. That evening I inspected the tires and wasn't pleased. The course is mostly right-handers so the left-front was the worst (http://img2.freeimagehosting.net/upl...292b18057.jpg). The right-front looks similar (same wear spots in center and outside) but not as severe. The rears have some wear in the center tread block and not so much on the sides. My most common mistake is bombing into corners and killing the front tires but I thought I was doing okay since I was heating all four tires evenly. So what do I need to do differently at my next track day? More pressure? Water down tires between sessions? Fix my driving (I'm still working on this)? Nothing?

Not sure what my alignment is since the car is relatively new; it's on my to-do list. I assume that it's within spec since the previous owner was pretty **** and steering is straight (and they all look like their in spec).

Razz1

You could go to a softer tire. It also depends upon if you are driving smoothly or jerking the wheel.

The smoother the better.

costello

Did you have a lot of tread on the tire before the event? I would suggest going to a different tire if you plan on tracking more often. The KDWs are ok, but most likely was not able to handle the high heat of the day and the 30 min sessions. It's not uncommon for tires to chunck during track events especially if they still have a lot of tread on them. Shaving the tire might help as it reduces the height of the tread blocks and tread squirm, but that seems to defeat the purpose of having a dual purpose tire.

You might want to look into a dedicated set of rims and tires for track events. The initial investment might be higher, but over the long run (especially if you start doing more track events), the cost is about even and you have good tires for the street.

Spin9k

Slow in, fast out sounds like a tired cliche but it isn't. Braking and entering too fast saves you the least time on the circuit. Work on the exits...it's faster and cheaper (less tire wear). I've not chunked a tire in 5 years ...even a little. But BFGs may be different I have no experience w/them.

SouthFL

300 UTQG treadwear tires will chunk.
Look for a street/track tire closer to 200.

alnielsen

iTrader: (4)

I have known others that have had chunking problems with the BFG KDW's. You have to run something like 45 psi cold to prevent the problem. I think the OEM tires make better track day tires than these.

RK

iTrader: (1)

Did you have an instructor with you? One of the first things autocrossers need to do when they get on the track is to forget everything they've learned about autocrossing. Everything has to be smoother from your braking to your accelleration. Whoever was sitting to your right should have been reigning you in. Nelson's is not in the greatest shape ever - I'm sure people were talking a fair amount about the new ownership there - so if anything you should have been taking it even easier than some other courses. It was probably more your tires than anything but they still shoulda been helping you out.

Are you in NE Ohio? Plenty of 8 owners around here. There should have been one up at the FunDay on Friday (Tony).

chiketkd

iTrader: (5)

Be careful when making a sweeping statement like that.

I was ALWAYS taught in autocross to be smooth with my steering, braking and acceleration inputs (at least that's what the Evolution School teaches). Maybe novice autocrossers go bombing into corners, but all of the top drivers I see running locally - Jinx, Strano, Salerno, Garfield, etc are all *very* smooth in their inputs on course.

dannyc

Thanks for the input. The previous owner of the car had the KDWs so I'm just running them through their paces. I'll probably try to get some Star Specs next since that's what the heavier street tire guys seem to prefer in autocross. Depending on my $$$ situation I'll may or may not get some R6s or V710s. How much do r-compounds wear at a track day? I've heard they last 80-100 autocross runs but a track session is significantly longer although there would be fewer heat cycles. Would a set of tires last me a full year? (~10 autoX events and 2-3 track days)

I've been working on smoother inputs and I had a couple more experienced drivers ride along, none of whom said anything about it. I was braking pretty early because I wasn't sure how the brakes would hold up. The tires seemed to complain the most under power coming out of the carousel which lasts FOREVER.

I'm from Pittsburgh. There weren't any other 8s there that day. I'll be at the HPDE event at BeaveRun in October. An instructor would probably help. Hopefully I'll meet a couple of you guys there.

Got a video from my first session. I was still searching for the right 'line' but my driving style probably didn't change much. Any suggestions appreciated. By the end of the day, I was keeping up with my friend in an S2000 who's tracked a bunch so that felt pretty good.

http://youtube.com/watch?v=gAFmVr9ZTBg

SouthFL

I'm running a set of first run Z1's myself (the pre Star Spec Z1), with a half dozen track days on them and there's, conservatively, at least another half dozen track days left in them.

RK

iTrader: (1)

Nice! I haven't been at Nelsons since '06 but I still remember every twist. Looks like crap on video and I can't wait until they repave/widen it but those turns are so much fun. You carry so much freakin' speed on those its ridiculous.

The only two things I picked up on different from the line I take is you seemed a little tighter on Oak tree. I would let my 8 drift a little higher, towards the middle, and then drop down on the apex of 6 at the end of Oak tree. It let you carry a little more speed into Carousel which usually means more speed out of Carousel.

The other thing was that you could probably brake a little later in turn 1. You seem to clip that apex a little early.

But it sure looked close to the line I was taking and overall you were doing a much better job then I did.

alnielsen

iTrader: (4)

As long as your not in competition, it is a waste to run r-compounds. They wear out faster and cost more initially. Plus you have to buy, transport and swap (at the track) a second set of wheels/tires. Also, you don't want to take them onto the street. An r-compound that will work on the race track will be too hard for autocross. With a good maximum performance street tire you can drive on the street and track. Save the money and put it else where in the car.

costello

I'll have to disagree with the statement that R-compounds being a waste. True, you're not racing so you don't need the fastest tire, but in my experience an R-compound can last for several events while saving your street tires for normal duty. For example, I have been using a set of Toyo Proxes RA-1s this last year. These tires have tread on them when they're new so I change tires at home and drive to the track on them (2 or 4 hour drive one way). I still bring my street tires in the back just in case of heavy rain. They have a total of 8 track days on them(4 at Sebring & 4 at Roebling Road) and I plan on running a couple more with them. My street tires are still pretty new and it's been about a year. I don't think any street tire would have lasted that long and by the end of their life you'd be driving around town on nearly bald tires. I don't think having an extra set of R-compounds will cost that much more in the long run when you start averaging things out.

If you're only doing 1 or 2 track events a year, maybe it's not worth it, but once you start doing more, having a dedicated set of wheels and tires is a plus.

Spin9k

I would not recommend R6s or v710s for HPDE track use. They're both expensive and relatively short lived. BUT I definitely would recommend any of a number of R-compounds one step down in grip from the aformentioned ones. Not only do they greatly improve the "fun level' of HPDE experience for moderate to advanced driving levels, but they provide a level of safety due to their high grip levels and forgiving nature.

As for transport and swapping tires at the track...how hard is removing the rear seats (3 min max) and loading in the tires? Changing tires is as simple as jack up one side, remove 2 tires, replace with r-comps...jack up other side..repeat.

I've actually had people offer to help me change them...it was fun in their eyes I think my record is changing back and forth 4 times in one day due to weather, but hey, what's a little expercise anyway? I watch race car teams change rear tires in 3 second on SpeedTV last weekend! I'm working on it....

dannyc

Good advice. Oak tree was tricky because there's all kind of crazy camber changes through it, I ended up choosing to apex right where there's the most camber on the inside. It's definitely a faster turn than I took it since it's actually an increasing radius exit.

Turn 1 was my favorite. At first (at the time of the video) I would brake really early since I didn't want to shift into 4th and back into 3rd so I would brake when it started hitting the limiter. But then I realized it's a much faster turn than it looks so I shifted and carried more speed. Took it too wide into the extra pavement at the exit once. It upset the car and I almost spun it

Nelson's is a fun and unique track. It's quite fast even with the bad pavement. I heard the plan is to slow it down after they repave it, especially after the carousel where most people go off.

RK

iTrader: (1)

That's exactly the way I started out on that turn. Fortunately for me my instructor happened to be my friend who happens to have at times had the fastest lap @ Nelsons. He grew up on that track and has the line down pat. So by the end of the first day I had my line down. After that it was just a matter of inching faster.

Interesting. The only things I've heard (mostly from Mid-Ohio 2 weeks ago) was that the new ownership will not be making it a country club course although they are the same owners that are doing that in the Virginia/DC/Maryland area. In addition they are ripping up the entire course and repaving - making the road wider to allow for 3 cars wide at most points in the track and making more runoff space. The configuration is supposed to essentially stay the same but they want to add some flexibility to change the configuration between clubs and races similar to how Mid-Ohio flips the bus stop on and off.

Guess we'll all see what it's like in the Spring.

dannyc

I was talking to a worker. He said they were going to add a dip or something to the exit of the carousel. And something about turn 4 but I don't remember what... Lots of rumors going around. The track would be *** fast if it were wider and smoother; it's already the fastest two mile circuit in the US or something.

BlueRenesis82

Those tires just chunk a lot, I had a set that I did quite a few track days on, and they have missing rubber chunks the size of a quarter.