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      04-15-2012, 09:13 PM   #89
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Got raw-timed by 3 tenths by an STU STi (.841 vs. .844 index, so not totally embarassing) . Getting more comfortable with what to expect from the car and what to expect is good turn-in and then a push until I can get back in the throttle to rotate with power. Hopefully correctable when the shocks come, if not I'll have to rethink a little
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      04-16-2012, 06:35 AM   #90
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Wow, that is a fast autox course.

My wife as on call this weekend and i ahd the kids, so i missed out on coming up to race. Wish i could have been there.
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      04-16-2012, 07:34 AM   #91
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Would have been fun, hope you can make it up for a different date! It was only 105 people this time, we had a threat of severe storms which kept a bunch of people away, but weather was perfect and the lot had just been washed down by heavy rain so the gravel was mostly gone and it was surprisingly grippy.

I grabbed third on the 5th run to see what would happen...it was not worth it, but yeah, fast course again
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      04-16-2012, 10:01 AM   #92
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Now THAT looked like fun. It sounded like you aren't experiencing any axle-tramp at the launch. I have to be very careful to avoid -- hence, no aggressive starts. I wonder if my shocks are tired (45k miles)?
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      04-16-2012, 10:10 AM   #93
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My car has nearly 33k on it, I don't have EDC, but these are fairly smooth asphalt lots, at least the launch areas have been smooth. I only ever get wheelhop on concrete or wet or bumpy asphalt.

So some thoughts on how the car acts with the current setup:

- Turn-in is good, I have all the tossability I need
- Steady-state neutral throttle kindof sucks. Needs help here.
- Very stable in slaloms, with good response to drop throttle, car is faster than me in slaloms
- Power-on oversteer at will, but it's very easy to control and never too much unless you're stupid. This is probably the only reason the car isn't terrible on course with the mid-corner push it has
- Brakes are awesome, and it rotates nicely on trail braking,which has also helped somewhat with the mid-corner push. No ice mode yet and I've intentionally gotten into the ABS with the wheel turned a few times to see what it'd do
- Car is way underdamped over big bumps. I'm certain the shocks will help here

Now I need to figure out what to do next. I might try a little less front bar at the next event but I hate to give up any front roll rate with as little camber as the car has. I should have my MCS 2-ways in hand by the beginning of May and my next event won't be for a month so I should have a few more tools in the tuning toolbox.

Still no shelf of death on the front tires after 10 runs, and temps are actually fairly even across the tires front and rear. I'm hoping to get to 20-25 runs and flip the fronts on the wheels.

Interesting side note: My wheels and tires were parked fairly close to grid, less than 100 feet, and I never got a TPMS warning. Last event I was gridded about 100 yards away from my parking space and the TPMS warning was on the whole time. Surely the signal can't be that strong?
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      04-16-2012, 10:20 AM   #94
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Quote:
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Got raw-timed by 3 tenths by an STU STi (.841 vs. .844 index, so not totally embarassing) . Getting more comfortable with what to expect from the car and what to expect is good turn-in and then a push until I can get back in the throttle to rotate with power. Hopefully correctable when the shocks come, if not I'll have to rethink a little
Thanks for posting.

That sure was a wide open course, which your car seems well set up for. In a tighter course you might not like the mid-corner push as much, but your shocks may fix that. If not, you might try the E93 sway bar at the back. That'll be more important if you move up in rear tire width, as you mentioned earlier.

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      04-16-2012, 01:54 PM   #95
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Your description of handling particulars pretty much squares with my observations about my car.

Related to your comment about the car being faster than you in slaloms; my impression was that the car was faster than I realized, because its softness and heft masked its superb reactions and made it hard to read. So, I found myself having to react a little instead of being in synch with it. There's a learning curve there, but general tautening via more aggressive dampers should really pay off.

Yeah, the brakes are super (seems like a BMW specialty). We just finished four seasons in an ASP Exige and the OEM brakes were a constant source of irritation.

"Shelf of death"?
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      04-16-2012, 01:58 PM   #96
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"Shelf of death"?
I'm guessing he's referring to the 45 degree angle of edge wear that forms between the tread face and sidewall with A6s run on less than ideal camber...he's some pics from my E46 stock days:


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      04-16-2012, 02:33 PM   #97
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Yup. I bought a pair of used 295's from last year's DS prosolo champ with 18 runs on them (basically one ProSolo and Nats). It has a marked shelf of death forming on what would have been the outside edges (I'll flip them obviously), but that was a car running the same camber as this car, with a traditional strut instead of the dual pivot setup we have. Keeping fingers crossed the suspension design makes a difference, we'll see.

CSBM5 - How many runs did it take to get there? Are those the 285/30 A6's?
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      04-16-2012, 03:14 PM   #98
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CSBM5 - How many runs did it take to get there? Are those the 285/30 A6's?
16 runs on E46 ZHP, H&R front bar, Konis, and pins out measly -1.2 camber. These were 245/35-18, and this was back in 2006.

Watching the launches in the video was interesting as I'm comparing it to my M5 where you have to really ease it out of the hole, depend on some initial engagement weight transfer and then (depending on tires/grip) modulate the throttle carefully in 1st gear. On A6s in the summertime, I can get it to hook really hard most of the time, but you still have to be careful of losing it and having to back out of the throttle a bunch and blowing the launch.

Still hunting for either just the right 996 GT3 (pretty much given up at this point) or E90 M3 w/o sunroof but heated seats, tech package, etc. Not planning on selling anything else at the moment, but the E46 and S4 are leaving in a couple of months. It's been a heck of a hunt the past three months (5 months on GT3, but I've given up looking for those, plus don't want to have to fool with the damn coolant coupling issues), and I let one 08 E90 with about everything except sunroof, 47k miles, still under factory warranty, etc, slip through my hands at $35k -- surprisingly it had original paint and no damage too. Oh well...

Regards,
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      04-16-2012, 05:06 PM   #99
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Launching it a little tricky, you can't go WOT right away (I'm at about 1/2 to 3/4 throttle for half a breath after the clutch engages) but not too bad on the hoosiers, much touchier on street tires. You need to haze them a little to keep from bogging but the broad powerband means you don't have to use nutty revs to be in the meat when it hooks. My friend with an S2000 needed 7k to keep from bogging the launch.
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      04-16-2012, 07:09 PM   #100
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Quote:
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Got raw-timed by 3 tenths by an STU STi (.841 vs. .844 index, so not totally embarassing) . Getting more comfortable with what to expect from the car and what to expect is good turn-in and then a push until I can get back in the throttle to rotate with power. Hopefully correctable when the shocks come, if not I'll have to rethink a little

Wow, fast course.
My local solo courses have at least 4 180 degree turns in them, which kills my M3 compared to the smaller cars. You can hardly accelerate before you are braking hard for a sharp turn.

You can really use your power on that course.
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      04-21-2012, 05:20 PM   #101
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      05-04-2012, 10:04 AM   #102
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So, got the MCS 2-way dampers here. Working through a couple things with the struts, but I installed the shocks and I'm amazed at the difference.

- Turn-in is better (with ~175psi in the canisters, more rear effective spring rate is probably the reason why)
- Mid-corner composure is a LOT better. Where the rear used to skip across bumps, now it just lays the power down. The only thing holding the car back from getting into the throttle in 2nd gear is forward traction, no more worrying about encountering a bump and throwing the car sideways. The change in how it handles bumps is astonishing.
- Dive under braking is much better controlled, the car eases down onto the front springs instead of slamming down on them
- With the shocks dialed back it rides better than stock, and the adjustment range seems huge.

Routing the canisters was surprisingly easy, I just cut a corner out of each vent in the side of the trunk. Didn't even have to cut the fender liner, though I did have to pull it to get access.

Can't wait to get the struts on!
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      05-04-2012, 02:42 PM   #103
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I've begun thinking about shocks, but am unfamiliar with MCS. Do they have a website?
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      05-04-2012, 05:24 PM   #104
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Http://www.motioncontrolsuspension.com

Former moton people who left during AST buyout. Bimmerworld and VS motorsports are dealers among others
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      05-06-2012, 08:24 PM   #105
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Event 3, including bumper cam and side-of-car cam and fastest run

Interestingly, the shocks worked best turned almost all the way down, otherwise there was a push on turn-in. Front struts can't go on soon enough!
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      05-15-2012, 09:29 PM   #106
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Had the car aligned prior to the last event, found out the rear camber and toe at both ends was not left-right symmetrical. Got the camber squared away, but the shop stayed within factory specs (communication problem), and I ended up with a little front toe-in and not enough rear toe-in. So, back to the shop (a good one) this week.

Lightweight wheels and yes, 315 rears, are also going on this week.

Talked to Bimmerworld about the MCS shocks. Nothing is in the works yet, but I certainly like their eagerness to please.

At the above-mentioned event I ran with the Power button "on" for the first time, for my last few runs. My E46 on street-grade tires was overwhelmed in that mode, so I had avoided using it with the E92 until I was acclimated to the car on R-compund tires. Bottom line: I think this car can use the quicker throttle response to advantage.

Rich, how are you mounting your camera?
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      05-15-2012, 09:53 PM   #107
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I might have to try the power button next time. Now that I think about it I haven't had many moments that felt like I was getting into the throttle too early.

I'm using the Chasecam 3-cup suction mount. It seems to hold pretty well, the camera is a fairly light old Canon digital Elph SD1100S (I think) which won't make me sad if it falls off or gets hit with a rock
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      05-15-2012, 11:17 PM   #108
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But where are you mounting it in the interior?
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      05-16-2012, 02:04 PM   #109
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Oh, sorry. I hate headrest mounts. So I hang the camera from the suction mount right in front of the windshield mirror to the right side of the mirror mount and flip the image in moviemaker. Next event which isn't until June 24 unfortunately I'm going to do a driver view, bumper cam, and I think I found a good place to do a suspension cam. Stay tuned, "race" fans.
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      05-16-2012, 03:26 PM   #110
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Ah -- flipping the recording in an editor certainly opens up mounting possibilities. Thanks!
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