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      04-16-2009, 12:33 PM   #1
JCz04Bimmer
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Watkins Glen (4/20 - 4/21)

So I'm headed to the track with the Z4MC for the first time this Monday and Tuesday! Couldn't be more excited but I'm also a bit scared of the power this car has. I have about 8 or so days at The Glen in my previous car so I'm quite familiar with the track which should help with getting into a mindset of understanding the car and its behavior and not being preoccupied with whether I make a left or a right. I'm going with COM for the first time and the second day, if I'm signed off, is time trials which will be a new experience for me.

I got my experience at The Glen in a modified 330Ci which had comparatively minimal power (~240hp) so it was really hard to get in trouble. Though motoring out of the Toe of the Boot was torture! I also had a TC Kline suspension and all sorts of handling enhancing modifications that made it impossibly smooth.

Anyway, in preparation for the event this weekend I'll be tackling a few tasks...

1) CDV Delete. I've had the blank for Zeckhausen for a while.
2) Ferodo DS2500 Pads. Got these from Zeckhausen as well and had them on my 330Ci previous. Excellent streetable but track-worthy pads
3) Motul 600. Standard issue track day task here.
4) Oil Change. Standard issue track day task, too. But I got a magnetic drain plug which is pretty sweet.
5) Ultimate Pedals. I picked these up with the extended upper left gas pedal. Should help with downshifts.
6) Ultra Lap Timer. Can't wait to start timing my laps to really let me know what I'm doing right and wrong.

I'll be running my SSR Comp-H street wheels in 19" fitment so its possible that I'll have the biggest wheels at the event. But they're wrapped in the phenomenal Bridgestone RE01R's so I'm not too concerned.

I'll be sure to post about the event and my experience with the beast...
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      04-17-2009, 01:41 PM   #2
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...looks like my first days behind the wheel of the Z4MC on the track will be wet! Looking forward to some seriously (unintentional) sideways moments...

(I think my street tires are looking better than ever now!)
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      04-20-2009, 09:25 AM   #3
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Given the wet weather, take it carefully. Especially on the toe, and the laces. For whatever reason, I always find myself staring at the headlights of the guy in front of me in the toe, who decided to backoff late in the corner, and ends up going off backwards in front of me. Have fun, and be smooth it is a core requirement.
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      04-20-2009, 08:30 PM   #4
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One day down and one to go! It was SUPER wet on the track all day but dried off for about a half session right before it kicked back up again. Smooth is where its at! I've always been a fan of being super smooth first and fast second but this being a new car with a whole mess of power it took some getting used to. But this being my 9th and 10th days at The Glen, at least I know the track.

At the start, I was taking the race line because my speed was so low so why not but eventually as I ratcheted up I had to stay away from the way too slippery concrete patches. I ran some pretty cool lines and had a great time. The Toe and Laces didn't give me much trouble but Turn 8 did give me some scary situations. Because its downhill through the brake zone I found myself carrying a bit too must speed and getting a bit unsteady under braking when setting up for the turn-in. The main reason why I was unsettling the car was that I started my braking right at a point where there's a slight drop off so the car was unloaded and light so the ABS would get all sorts of bent out of shape. I adjusted my brake zone and things seem to be a better now. Managed to clip 130 on the back straight which I think is pretty damn fast considering at times it was impossible to tell if someone was giving a point-by because of all the spray!

I'll report back on how things turn out tomorrow. It's supposed to be marginally better weather.
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      04-21-2009, 11:59 PM   #5
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Just got in. Tons of fun. The second day was totally dry. I'll provide an update sometime tomorrow...

I will say that I have to get new ignition coils on cylinders 1 and 6. During the last practice session, I threw a Service Engine Soon light and basically was in an unofficial limp mode with severely degraded power. Engine was chugging along, too, so it seemed like two cylinders decided to misfire. I checked the codes and that was what happened. I cleared the codes and the car started fine. On the time trial session, it happened again and the car was back to normal by the time I had gotten back in to the pits without even turning the car off and on. Both times it happened in the braking zone coming in to the Bus Stop. I'm not the smoothest heel-toe-er so I think the less than smooth downshift tripped up two already on-their-way-out coils. Both times it happened it was on 1 & 6.

Oh, and our rotors make goofy snapping sounds when used to their potential. A friend with an E92 M3 that has similar brakes (drilled, etc) had the EXACT same phenomenon.
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      04-22-2009, 06:43 PM   #6
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Sounds like fun. Odd on the coils. Hard braking should have any effect on the coils. The Glen is a hoot. I won't likely see it again until late summer, in the 968. Keep us posted on how it works out.
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      04-23-2009, 02:18 PM   #7
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Some observations.

Because Day 1 was exceedingly wet and cold, I got a very quick lesson on how the Z4M behaves in less than ideal situations. You can be doing everything perfectly and still get in to trouble in the kind of conditions we had but it really gives you (pardon the term) a crash course in your car's dynamics and near-limit behavior. In the dry weather, I'm probably not good enough to get to its limits but in wet weather I was certainly getting there.

Grip in the wet was acceptable. Sometimes intermittent but actually acceptable. I was running street tires, the Potenza RE01Rs, so I was obviously better off than some of the R-Compound running cars. Traction controls stayed on and I never went beyond 75% of brake application. I definitely WOT'd it, though. The traction control was shockingly not intrusive. I am a notoriously smooth driver on the track so that could be a factor but only a few times did the light come on and when it did it never was too aggressive with its efforts. Braking was interesting. At about 60-65% application, I was able to get decent performance in the brake zones. If I went any further a portion of the brake zone was spent dealing with ABS coming on. Generally, the car tracked straight and didn't get to squirrely. In some of the downhill and/or unloaded braking zones, the ABS would come on and the car would slide off line. Wee!! But the car never got entirely out of hand.

One thing that was impossible given the conditions was any attempt at trail braking. The car just hated trail braking in the rain. For the Fast Left (Turn 10?), I usually pop the brakes on for a moment right when I'm turning to get the speed down a bit and rotate me in to the turn. In the dry, this is an extremely fun way to take the turn. In the wet... not so much. I tried this at a lower speed, obviously, and the car's back end came around completely. I was able to save it with some throttle application and counter-steering but when I gave it another shot the same exact thing happened again. The guys on Top Gear probably just would have stuck with the slide and even things out but I was on a track with other people and corner works so I didn't feel it was appropriate to get all drift-master-flex on everyone. Not that I can even pull that sort of maneuver of, but you get my point.

Overall, the car was quite impressive even in the rain.

So fast forward to the dry day. It was still quite cold (maybe about 50?) but it was dry and by the second practice run I was getting some good heat in the tires and brakes and was able to really open it up. The car, as expected, is a beast. Smoothness is essential if you want to go around the track in a metered and even-keeled manor. However, with a bit more aggression in your right foot, the car is impossibly fun. The second session of the dry day was my chance to really see what the car does when I push it. Granted, my pushing was probably only barely approach half this car's potential but it was nonetheless a thrill. Unlike my 330Ci on the track, the power the Z4M is intoxicating. And even with a full stock suspension setup, it turns-in politely, attacks the apex with confidence and tracks-out quite neatly. If I was abrupt on getting on the gas at the apex, the back end slid a bit but the 50/50 weight distribution gives you an odd confidence in where you'll end up.

As mentioned, at the end of the second session on day 2 I started throwing misfire codes on cylinders 1 and 6. I believe that both times it occurred as I was entering the Bus Stop which requires significant braking and a downshift. Not sure if that's related but it was consistent. One thing with this car is that you need to be super smooth with the downshifts or the car gets upset. I'm not the best heel-toe driver but messing up downshifts in the Z4M is ugly. The tires chirp, the ABS comes on -- overall, unsettled.

But despite the issues I had at the end of the event, my first track days in the Z4M were great. I'll be returning the The Glen at least 2 more times this season and hopefully I'll make it to some NHIS events with COM, too. Oh yeah, this event was with COM Sports Car Club. Excellent group of people and excellent school.
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