E92 M3 ZCP in SCCA Solo F Street

[Blue Gumby]

I'm going for an alignment Saturday, anyone care to share some specs? I already pulled the pins in the front for max camber. Was thinking a little toe out in front, like .03.

[thasuperdude]

Originally Posted by Richbot

...Your sig says '09, no ZCP for you.
I recommend the Dinan bar, I think it's higher quality than the bar I have, the RD Sport bar, though I haven't had any issues with mine. Say yes to the front bar.

Great info. Thank you. Yes, 2009, I only have 2 buttons to play with

What mm bars do most people run?

[thasuperdude]

Originally Posted by Blue Gumby

I'm going for an alignment Saturday, anyone care to share some specs? I already pulled the pins in the front for max camber. Was thinking a little toe out in front, like .03.

A little tow-out in the front and a little tow-in in the rear makes a world of difference on the auto-x course, but very active at highway speeds. Get as much neg-cam as you can achieve.

[Rexpelagi]

Originally Posted by thasuperdude

Great info. Thank you. Yes, 2009, I only have 2 buttons to play with

What mm bars do most people run?

The Dinan bar seems to work very well - 32mm.

Originally Posted by thasuperdude

A little tow-out in the front and a little tow-in in the rear makes a world of difference on the auto-x course, but very active at highway speeds. Get as much neg-cam as you can achieve.

Toe*

I typically run 0 toe in the front, as the math doesn't make sense to me why toe-out is better (I know that is the general rule though). Toe-in is no doubt the answer for the rear. I didn't align the one I drove, nor do I have the specs, so I'm not sure how much you will want.

For camber, you should get about -1.7deg front with the pins pulled, and will probably want around -1.2deg rear (stock is probably closer to -2deg).

[CSBM5]

On my 2011 non-ZCP E90, I got -1.4° LF and -1.6° front camber with the pins pulled. ZCP cars I believe sit 10mm lower hence probably pick up a maybe 2/10ths more negative camber (?).

FWIW, the factory alignment specs for the M3 according to the printout from my dealer are:

front camber: -0° 43' to -1° 33' which converts to -0.72° to -1.55°
front toe: 0°01' to 0°09'

rear camber: -1° 33' to -2° 03' which converts to -1.55° to -2.05°
rear toe: 0°01' to 0°09'

I ended up doing a street alignment with 0°04' toe each side up front and 0°05' each side rear. Looks like the factory spec basically allows for zero toe since 1 minute of toe is miniscule (i.e. 0.017°). I'm not sure how much I would gain from 4min (0.06°) less toe up front, but I decided it probably wasn't worth potential issues with tramlining or less than solid directional stability at highway speeds and such (perhaps an invalid worry).

Regards,
Chuck

[thasuperdude]

Originally Posted by Rexpelagi

Toe*

Doh... I didn't notice my slip

[Blue Gumby]

Quick update. After the alignment I got 1.3/1.4 camber in front and tried 1.8 camber in rear. 0 toe front and .2 degree toe in for rear.
First autocross of the year on 275 (18") Z2* on 32 degree weather. Dinan bar at stiffest settings. Started at 42 front and 40 rear, non ZCP. Massive roll over in front like past triangle and rear was 1/2 triangle.
Massive grip from first run onward. Tire is very quiet, never really slipped. Handled very well overall. Bumped the pressure up to 46/44, car felt the same but did not have chalk to check roll over.
I think this is where ZCP have a big advantage with wider rims. They don't have to run as high pressure due to wider rim and more camber. First event with the car so getting use to the throttle is tricky coming from the NC Miata. Overall I'm very happy with the car so far.
I did have some oil show up on passenger fender liner. I pulled the fender but can't locate the leak. Any suggestion where to look?

[CSBM5]

I just did my first event of the year Sunday, and temps were super low here too...low enough I was worried a bit about the tires on the way to the event (19F). By the time of my run in the 1st group, it was 30F and was 33F at the end of the group.

Wow, those seem to be high pressures. I'm running 275/35-18 Rivals all around, and I shoot for 35psi hot all around, sometimes allowing the fronts to go up to 37psi. Rollover isn't real bad up front, but the Rival has the wrap around tread also. PAX'd 5th overall. I'm running the original solid/non-adjustable Dinan front bar, and with the pins out camber up front and square tires, I can't fathom driving this car without the big front bar as it would have to be too loose. I could have used 295s in the back Sunday on a long sweeper...at least would like to try them out sometime.

[chono]

Originally Posted by Blue Gumby

I did have some oil show up on passenger fender liner. I pulled the fender but can't locate the leak. Any suggestion where to look?

I'm guessing its not oil. Its probably power steering fluid.
Run with fluid at the lower fill marker and it shouldn't find its way out the bleed hole.

-'chono'

[Blue Gumby]

Originally Posted by chono

I'm guessing its not oil. Its probably power steering fluid.
Run with fluid at the lower fill marker and it shouldn't find its way out the bleed hole.

-'chono'

Thanks! I'll look into that. I hope your right.

I do have Rival-S on order but they won't come in until 4/20 as most of you guys probably know.

[z3papa]

I must be operating from a different universe on tire pressures. On 255/285 RS3's in 45-50 degree temps and using a Longacre probe pyrometer, I had very even readings across tires and was at or above the arrows with 35F/31R. Taking Rich's advice, I straight lined braking, did not overcook entry and rolled throttle at mid-apex.

Given that we had 20~ or so Nat'l competitors both days and where I indexed, I know I was pushing it. While I'm certain pressures may bump 1-2# per axle in warmer higher grip events, that would put it at 36-37F/33R. I think staggering the pressures to less in the rear is going to make hard throttle corner exit all the more controlled.

[Rexpelagi]

Originally Posted by z3papa

I must be operating from a different universe on tire pressures. On 255/285 RS3's in 45-50 degree temps and using a Longacre probe pyrometer, I had very even readings across tires and was at or above the arrows with 35F/31R. Taking Rich's advice, I straight lined braking, did not overcook entry and rolled throttle at mid-apex.

Given that we had 20~ or so Nat'l competitors both days and where I indexed, I know I was pushing it. While I'm certain pressures may bump 1-2# per axle in warmer higher grip events, that would put it at 36-37F/33R. I think staggering the pressures to less in the rear is going to make hard throttle corner exit all the more controlled.

While that might be a touch low for R-S3's, I think anything over 32-34psi is too high for the ZII (coming from other applications).

@Blue Gumby - If they are rolling over at 40+psi you may want to adjust your driving - you might be unnecessarily abusing the front tires with some odd inputs or overly-aggressive driving.

[Richbot]

I suspect his gauge is off. I didn't even have to run Conti DW or PS2's that high.

I have had "good" analog gauges from companies like Longacre read up to 6-7 psig off from standard. I have never had a digital gauge read off standard.

I have also always ended up with a pretty good split, like 4-5 psi front to rear (higher in front). Car seems to like a little less rear pressure maybe because like many of you I'm running a little more camber rear than front.

[UNCbigM]

Interesting, when it was reasonably warm, ~50s and 60s, I started at 37f/35r but eventually settled on 35/34 on ZIIs on sealed pavement. I'm curious about a larger gap F to R as Rich mentions...

[Blue Gumby]

Is everyone putting 275 on 8.5/9.5" rims?

[UNCbigM]

That's what I've got...

[CSBM5]

Originally Posted by Blue Gumby

Is everyone putting 275 on 8.5/9.5" rims?

That's what I've done...working out fine.

Reposting pic: 8.5 on left, 9.5 on right:

[mills84]

Why is there no street touring class for the e9x m3?

[Rexpelagi]

Originally Posted by mills84

Why is there no street touring class for the e9x m3?

There is - STU. And, unfortunately, good luck with that...

[z3papa]

Originally Posted by mills84

Why is there no street touring class for the e9x m3?

Not to derail this thread into another discussion but you will want to really assess how much you get from allowances, their cost and impact to the car versus how much other cars get from those allowances. I went deep down the hole in my STR car and would not be inclined to do it with my M3 even if it meant having the option to get camber plates and faster vehicle.

[mills84]

Originally Posted by Rexpelagi

There is - STU. And, unfortunately, good luck with that...

This is the list straight from the website. What does the NOC imply?

[Rexpelagi]

Originally Posted by mills84

This is the list straight from the website. What does the NOC imply?

NOC = "Not Otherwise Classed"

Translation: "All E9x's go to STU unless they are classed in another ST class, including the M3"

For example, the E92 328i is already in STX, so that is "otherwise classed" and wouldn't fall into STU.

Originally Posted by STX Rules

BMW
128i (2008-13)
3 Series (E30 chassis, incl. M3)
3 Series (E36 chassis, non-M)
3 Series (E46 chassis, non-M)
3 Series (E9x chassis, non-M,
non-turbo) (2006-13)
M5 (E39) (1998-2003)

The competitive STU RWD cars can fit 18x11's and 285's within the stock fenders, and should weigh 30xx-31xx lbs (ie, Corvette and 350Z). Obviously the Corvette makes power too. The E9x M3 would be fine for locals and if you just wanted to have fun, but I don't see it as a national threat.