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      04-26-2010, 02:07 PM   #1
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Track report Summit Point Main, April 21st

A bunch of my friends and I went last week to the Colonial Challenge Cup (a charity event) at Summit Point, on April 21. It was my first time with this crowd and loved every minute of it - there was a great diversity of cars, much more than you get at a car club's event. My friends all ran in novice (first time on track) and I ran in intermediate.

The morning sessions were in the rain which is where the M3 proved to be an absolute delight. I was reminded that I made the decision to get an M3 over a 135i after driving it in the rain on narrow, slick and bumpy country roads at Watkins Glen Oktoberfest.

Summit has recently laid some new asphalt in the turns on the Main track, which proved to be incredibly slippery and a big challenge to drive fast in the rain. In the first lap I was just telling my instructor I was a tad nervous about driving such a powerful car in the rain, when I was rudely interrupted by two interesting moments on track. It could have been scary and inhibiting, but instead the car was so easy to catch and gave so much feedback that I immediately became more confident and started pushing.

I have to say that those two sessions in the rain were an absolute blast, some of the best track driving I've ever done. I passed or lapped pretty much everybody except a highly modified Mk V GTI who was fast/good. That doesn't mean I didn't make any mistakes - did plenty of those - but the car was so confidence inspiring and predictable that I just felt comfortable pushing it - and myself - a lot more than the rest of the guys out there.

One driver complained to my buddies that I sprayed their cockpit with water as I passed, which may sound funny initially but could be very unnerving when it happens so I tried to keep more distance when passing in subsequent sessions.

I was running all stock except for Carbotech XP10 at the front and XP8 at the rear (thanks Lucid) which held up reasonably well. I'll probably do XP10 all around next time, or even XP12 plus brake ducts because when pushed the car could go well over 145mph on the straight.

The confidence inspiring trend continued in the afternoon when it was all dry and sunny. Everybody picked up a bunch of speed and so did I - lots of it in fact. Things started happening with a totally different rhythm and at a different pace so the main areas I've identified that need immediate improvement are: braking consistency and heel & toe on 4th-2nd downshifts. I'll be looking for a louder exhaust probably, I just could not hear the engine which probably accounts for the majority of the heel & toe deficiency.

Now I know we were all there to learn and have some fun and that we weren't really racing, but it felt *massively* good to pass a Ford GT, after catching up to him and following him very very closely for about 3 laps. His lines were a little off but the car's massive grip and grunt were masking this to a great extent, and I had to be always as close to perfect as I could to keep the pressure on him. But I did, and eventually he gave me the point by - a moment of great jubilation for my instructor (greater than mine at the time, I was very concentrated). Again, the only car in the group that I didn't pass was the GTI and I was never passed during the whole day.

My friends all did as expected and all came back with a totally new appreciation for their cars (2 x E46 M3's and one C6 Vette). Needless to say they've been bitten by the bug and are now feverishly planning for the next track outing.


Another highlight came with the charity rides - for $25 you got 5-6 laps in some exotic/interesting car: F360 Challenge Stradale, Vette ZR1, 911 GT3, E30 M3 set up for drifting and last but not least a supercharged Atom. I bagged rides in the Ferrari, the ZR1 and Atom all of which were extremely interesting for different reasons:
- The F360 gave tremendous feedback, even I could tell at all times what the car was doing. Plus, it had the most absolutely fabulous brakes I've ever experienced (he was braking from similar speeds as I, but where I started at the 1st marker he would wait until past the 3rd one).
- The ZR1 had just over 1000 miles and was barely broken in so he was not pushing it all the way - did most of the laps in 3rd and the occasional 4th. Yet it was the fastest thing out there, easily topping off 150-160 on the straight and offering massive grip in the corners. But not a lot of feedback (you simply need to trust the car) and the seats are horrendous (no support at all).
- The Atom was the most exciting of them all, absolutely brilliant. The engine note was somewhere between bumblebee drone and crazed dentist drill/alien spaceship engine. There is no inertia and your head will bang the headrest mercilessly - when it happens over 60-80mph it also places the top of the helmet into the slipstream which starts the buffeting and the upwards suction. Everything - fittings, welds, components - is of the best quality, you are definitely getting your money's worth. You can of course see the asphalt rushing by, the wheels turning and suspension moving - which in addition to being indescribably cool also helps you place the car with the greatest precision. A cracking drive. I want one, badly.

All in all a successful and fun day - the E90 M3 proved to be the fastest car I've tracked so far and the easiest to drive fast. Highly recommended.
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      04-26-2010, 03:05 PM   #2
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Forgot to mention how the M3 behaved, in no particular order:
- Less understeer than pretty much any other stock BMW I tracked, very balanced
- Very throttle-adjustable (once settled with the suspension, you can throttle-steer it all the way)
- Reasonable amount of roll (might possibly have a little too much roll if equipped with track tires, my guess)
- Very precise steering made it easy to place the car
- Engine and throttle response absolutely incredible (but would love it if the revs fell even faster)
- Cries for a Schroth quick-connect harness (I had a CG Lock and set the seat bolsters as tight as possible but still not enough)
- Oil temp never went over 220, no excessive oil consumption detected
- Did 4 session (20-25 min each) on one tank of gas, the low gas light came on on the last cooling lap
- Ran the EDC in the hardest setting all day long
- You can definitely feel the mass, especially in braking and very quick transitions
- Capable of *big* speeds on short notice - the rear is grippy and hooked so the car keeps picking up speed pretty much everywhere


Weakest point - the brakes. I hope to finish my version of the DYI cheap cooling ducts before the next track day.

Overall it's a good car - adjustable and forgiving, makes you look like a hero.
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      04-26-2010, 05:17 PM   #3
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Thank you for your write-up, looks like you guys had a fantastic time. Never been to summit point, but definitely hoping to do that track this summer!!

-Anderson
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      04-26-2010, 06:20 PM   #4
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Originally Posted by noxredna View Post
Thank you for your write-up, looks like you guys had a fantastic time. Never been to summit point, but definitely hoping to do that track this summer!!

-Anderson
Thanks, Anderson.

Just be aware Summit is actually 3 different tracks:
- Jefferson: small (9 turns, 1.6 miles I think), can be run in both directions - a little too small for me but excellent starter track
- Main: 2.3 miles, 10 turns, can be run in both directions - fast and flowing, 3 passing zones, murder on the brakes and outside tires
- Shenandoah: 2.x miles, 17 turns, very narrow and technical, has Corkscrew and Karoussell imitations - some love it some hate it, very demanding physically when driven fast


I'd like to do Shenandoah next (never done it in an M3) and NJMP.
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      04-26-2010, 06:34 PM   #5
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Nice write up! Sounds like you (and your buddies) had an awesome day. It really is amazing how great our cars handle in the rain and on a wet track (especially with the traction control off). Every event I have been to in wet conditions the M3's seem to distance themselves from the pack (including an R8 at one event).
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      04-26-2010, 06:55 PM   #6
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Originally Posted by Jaypod View Post
Nice write up! Sounds like you (and your buddies) had an awesome day. It really is amazing how great our cars handle in the rain and on a wet track (especially with the traction control off). Every event I have been to in wet conditions the M3's seem to distance themselves from the pack (including an R8 at one event).
Yep. Confidence and predictability were key for me.

I've tracked my 335i in the rain and it was a nightmare.
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      04-28-2010, 11:20 AM   #7
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Glad you had a good track day and the pads worked out for you. Just to clarify, I pads I sold you are XP12 front, and XP8 rear. There is a question if the rears might be XP10, but the fronts are XP12 for sure.

http://www.m3post.com/forums/showthread.php?t=352623

XP12 is probably the right compound for this car...
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      04-28-2010, 12:02 PM   #8
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Glad you had a good track day and the pads worked out for you. Just to clarify, I pads I sold you are XP12 front, and XP8 rear. There is a question if the rears might be XP10, but the fronts are XP12 for sure.

http://www.m3post.com/forums/showthread.php?t=352623

XP12 is probably the right compound for this car...
Got it.

Since I have your attention, I would like to ask a question - I've gotten (in the past 2-3 events too) a significant amount of brake shudder (vibrations) on hard braking. As far as I understand, these are caused by uneven pad deposits. They typically show up at some point in one of the sessions (2nd?), become progressively worse as the day unfolds and finally go away after a few days (with the most improvement coming from driving home with the now-cold track pads on). Forgot to mention, I didn't get any fade at all.

But I'm very careful about braking in the last (cooling) lap, about praking the car in the paddock after each session etc.

Could it be perhaps my braking style? Am I braking too hard, or perhaps not hard/short enough (and thus riding the brakes too much)? Is it pretty normal for my run group? Should I hurry up and finish my DYI brake cooling ducts?

Any insight is greatly appreciated...
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      04-28-2010, 07:07 PM   #9
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I don't think there is a such a thing as braking too hard. If you are in a major braking zone such as the end of a straight, you are meant to brake as late and hard as possible (threshold braking). If you are braking too early and softly, you are simply losing time; I don't see how that causes brake shudder.

A few potential issues I can think of:

1. Are you bedding in the pads before your track day? If you are not bedding in the pads, or bedding them in improperly, that can most likely cause shudder.

2. Some kind of incompatibility between the existing deposits on the rotors from previous pads and the track pads you are using. The carbotech rep mentioned something in those lines to me way back when I told him I was moving from Pagids to XP12 while ordering. He said I would have to clean the rotor surfaces, but I never did, and I didn't have any issues (I did bed the new pads in though).

3. Uneven rotor surface. I undertand the issue goes away over time, and that suggests your rotors are generally fine, but if the surface is not even, I guess it might be possible that during hard braking, you get uneven deposits. (This is somewhat of a wild guess).

Also, do you feel the vibration in the steering wheel, the pedal, or both?
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      04-28-2010, 07:21 PM   #10
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It happens to me all the time with stock pads and rotors, even when I don't use the parking brake between sessions. Usually, I don't feel it too much until the morning of the third day, after the rotors have cooled down overnight. Then there is a strong shudder. I guess the rotors are not evenly coated just because you don't always apply the same pressure for the same length of time.

Not using the parking brake at the track does not completely eliminate the problem, but it does delay the appearance of the shudder.

Last edited by drivendriver; 04-28-2010 at 07:27 PM.
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      04-28-2010, 07:38 PM   #11
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nice writeup..the charity ride thing sounds fun...would like to do that some time. Too bad about the pad deposits...I was just going to post and ask you if the aftermarket pads prevented that. That's essentially what happens with the stock pads as well...at least on my e46 m3. They finally wear themselves off, but it takes a while. I ended up going with the Pagid Orange I think it was and those did not create deposits, but could not be used for the street, although I did drive to and from the track with them. Would love to drive an aerial atom someday.
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      04-28-2010, 07:57 PM   #12
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Would love to drive an aerial atom someday.
Since I was at VIR on a business day earlier this month, between sessions I went to visit the factory. Very neat and clean. These cars are beautiful in their simplicity.

They have a "demo car" (their words), but they didn't offer me a test drive . At some point I'll have to ask them what you have to do to drive one, or if they're planning on reviving the "Ariel Atom Experience" track days.

They did give me a full price list for all the options. Also, the person we talked to claims that VA is one of the states where it's easier to register and insure an Atom, which only made the car more tempting.

Sorry for the thread highjack.
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      04-28-2010, 10:50 PM   #13
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Gotta love PS2s in the wet. What a great tire. An unfair advantage.

---------------------------
I drove Summit Point main in the rain on Apr 26th when it was wet for 3 out of the 4 sessions. I discovered something different than the OP regarding the repaving/patches. The patches are on the racing line in all of the turns except turn 2.

I found that the patches actually provided more grip than the regular track surface. This was particularly obvious in turns 1/2 and turn 9 while under power accelerating onto the straight from the apex to the track out point. While on the patch the back end stayed planted while allowing for acceleration while finishing the turn, but as soon as I got off the patch the backend got a little loose and wouldn't allow me to use as much power as I wanted until I straightened out the wheel.

The strange thing is that the patches were shinier than the other track surface, which normally indicates that they are more slick, but in fact, there's more grip on the patches.

The new pavement was put down at the beginning of April, so I wonder if the 5 days between the OPs experience and mine allowed the asphalt to cure more and thus changing the grip level in the wet.
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      04-29-2010, 09:29 AM   #14
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Quote:
Originally Posted by lucid View Post
I don't think there is a such a thing as braking too hard. If you are in a major braking zone such as the end of a straight, you are meant to brake as late and hard as possible (threshold braking). If you are braking too early and softly, you are simply losing time; I don't see how that causes brake shudder.
Yeah, that was pretty much what I was thinking.

Quote:
1. Are you bedding in the pads before your track day? If you are not bedding in the pads, or bedding them in improperly, that can most likely cause shudder.
I bedded them in before going to track, the evening before. Of course, by the time I arrived at the track the rotors were clean again, so I attempted to bed them in again just a few miles from the track. My buddies kept cover from traffic behind and I did 5 hard stops from 80mph. Problem could be, I think, that's not sufficient for the XP12 pads. As I understand it when bedding the pads in you're supposed to put a sufficient thermal load on the pads that they begin to fade a bit, after which you strictly follow the cool down procedure (don't touch the brakes for the next 10 min).

It simply may be a lot harder to do with these race pads than what I'm used to.

Quote:
2. Some kind of incompatibility between the existing deposits on the rotors from previous pads and the track pads you are using. The carbotech rep mentioned something in those lines to me way back when I told him I was moving from Pagids to XP12 while ordering. He said I would have to clean the rotor surfaces, but I never did, and I didn't have any issues (I did bed the new pads in though).
I'm pretty sure by the time we arrived near the track, the rotors were clean. Cold track pads and mild braking have this effect as far as I know.

Quote:
Also, do you feel the vibration in the steering wheel, the pedal, or both?
Steering wheel and brake pedal.

Quote:
Originally Posted by drivendriver View Post
I guess the rotors are not evenly coated just because you don't always apply the same pressure for the same length of time.
That's what I was thinking. I got very few completely clean laps, most times I was coming upon a slower car and had to adjust my (aggressive) braking pattern to their (more timid) ones. In other words, I had to apply the brakes 2 or even 3 times for each braking zone, where on a clean lap I would only apply them once.

But I'm also thinking I don't apply the correct and even pressure all the time. Braking is definitely something I need to work on, brake shudder or not.

Quote:
Originally Posted by EJ_92606 View Post
Too bad about the pad deposits...I was just going to post and ask you if the aftermarket pads prevented that. That's essentially what happens with the stock pads as well...at least on my e46 m3. They finally wear themselves off, but it takes a while. I ended up going with the Pagid Orange I think it was and those did not create deposits, but could not be used for the street, although I did drive to and from the track with them.
Were you bedding in the Pagid Orange pads?

At this point I'm assuming that all track-only pads have similar characteristics and brand/model is not that important anymore. Perhaps I'm mistaken?
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      04-29-2010, 09:34 AM   #15
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Originally Posted by skierman64 View Post
Gotta love PS2s in the wet. What a great tire. An unfair advantage.
In the rain I'll take all the advantage I can get.

Quote:
The new pavement was put down at the beginning of April, so I wonder if the 5 days between the OPs experience and mine allowed the asphalt to cure more and thus changing the grip level in the wet.
Possible. Also possible that the rain on the morning of April 21 (after days of clear weather) started to bring out the oils to the surface of the new asphalt.

We were warned in the driver's meeting about them, after the instructors had a chance to test the track - but I had a big slide right there in Turn 1 on the first lap, then another at the Karoussel etc. I just learned to anticipate them and use them when needed to turn the car. It was fun.
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      04-29-2010, 10:25 AM   #16
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Yes, you need to get them to temp for bed in, but I don't think you are supposed to toast them either. 5 stops seems too few to me, but you should check with Carbotech to see what they recommend for these pads.

On occasion, I have gotten some shudder while using track pads, but they have just gone away after a few laps. Nothing that persisted after the event after using track pads. On those occasions, I suspect I had not bed the pads in very well, but can't recall the details.

I asked about vibrations in the steering wheel because I wanted to see if this might be related just to your rear axle/pads (since those are most likely XP8), but doesn't seem to be case.
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