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Discussion Starter #1 (Edited)
Background: I am an old racer (since 1973) and have recently purchased a 2007 Z4MC. It doesn't require much, but I am minded to try and optimize handling, and am thinking about replacing the factory springs and shocks with BC Racing units, based on my previous experience with that product on other cars.

Problem: I see alignment specs ranging over 2-3 degrees of camber and from 0 to significant toe.

I will not be tracking this car, but do enjoy being able to drive briskly on winding roads and am posting to ask what specs people have found optimal for this model for occasionally aggressive street driving.

Note: specs from solo events are almost always incorrect for street use - usually wanting less front roll stiffness and different toe/camber. Track racing specs backed off a bit are more likely to be a good compromise for what I will be using the car for.
 

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Hello, congratulations on your M Coupé. I also have one and took it to the track for the first time a few months ago. The car struggled a bit on the run flat tires and I had quite a bit of understeer.
You can probably reach out to these guys as they specialise in BMW track cars

http://www.motorsport24.de/

Also consider using nitrogen in your tyres if you do not yet use it.

Enjoy your car.
 

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I think most people here will tell you BC racing is junk. Spring for the KW clubsports or at least the H&R's. You'll also need a complete suspension refresh since these cars are so old - replace all rubber, upgrade to polyurethane FCABs, etc. Check engine and tranny mounts. You may also want to consider camber plates for what you're describing here because you can't adjust the stock suspension all that much.
 

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Hello, congratulations on your M Coupé. I also have one and took it to the track for the first time a few months ago. The car struggled a bit on the run flat tires and I had quite a bit of understeer.
You can probably reach out to these guys as they specialise in BMW track cars

http://www.motorsport24.de/

Also consider using nitrogen in your tyres if you do not yet use it.

Enjoy your car.
I thought the M's did not come with run flats....unless you or a previous owner put them on?
 

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Look at KW coilovers.

Hello, congratulations on your M Coupé. I also have one and took it to the track for the first time a few months ago. The car struggled a bit on the run flat tires and I had quite a bit of understeer.
That must be a strange handling car with run flats on the M suspension, no wonder why the car was struggling. I'd switch to the proper non-run-flat tires for your M.

I thought the M's did not come with run flats....unless you or a previous owner put them on?
+1
 

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Discussion Starter #6
Yeah, surprised to see anyone with run flats on an M. I just replaced my tires and will do discs and pads in the Spring, while thinking about anything else that I want to do.

Contrary to what you may have heard, the BC Racing shocks are quite good and also get sold under other brands, I understand. I've had them on my Solstice for the last 5 years and they have performed very well for me.

I am a bit ambivalent about feeding the spring, as well as shock loads through the BMW rear shock mounts, but it appears than many have done that without issues.

I already have new engine mounts and transmission mounts on hand, to go in when I start driving the car next Spring.

If I decide that I need more front camber than the adjustment allows, the Rogue stand offs for the bottom of the front struts look like a nice creative way to accomplish that.
 

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S54=Living on the Edge
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If you don't plan to track the car at all, the KW V3's are the ticket to comfortable daily driving with great handling. And it does well enough for the occasional track days. The KW Clubsports are on the stiff side and you do sacrifice ride comfort on poor roads; plus KW does not have warranty on these while the V3's have lifetime.

As for camber, stick to stock alignment setting in the back and no more than -2° camber in the front (with zero toe). This should make turn in awesome and keep inside wear on the highway on the low side.
 

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Discussion Starter #8
As for camber, stick to stock alignment setting in the back and no more than -2° camber in the front (with zero toe). This should make turn in awesome and keep inside wear on the highway on the low side.
Thank you!
 

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What I've found after pulling the alignment pins, I could get 1.8* in the front (zero toe) and 0.8* in the rear with (1/8 total toe). It helps quite a bit on stock suspension. What engine/trans mount did you go with? I had luck with Rouge trans and Vibra Technics engine mount. I'm considering AST4150 or Bilstein PSS10 for the spring time.
 

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Discussion Starter #10
What I've found after pulling the alignment pins, I could get 1.8* in the front (zero toe) and 0.8* in the rear with (1/8 total toe). It helps quite a bit on stock suspension. What engine/trans mount did you go with? I had luck with Rouge trans and Vibra Technics engine mount. I'm considering AST4150 or Bilstein PSS10 for the spring time.
I went with the Vibra Technics motor mounts and some trans mounts from UUC. They go in next Spring. Put the car into hibernation mode today!
 

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Keep the car stock. Make your alignment a little more aggressive (like pal states) and leave it alone.....

As a track driver and instructor, the stock car is just fine. Don't waist your money...
 

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Discussion Starter #12
Keep the car stock. Make your alignment a little more aggressive (like pal states) and leave it alone.....

As a track driver and instructor, the stock car is just fine. Don't waist your money...
The more I drove it the more I am tending to agree. Thanks.
 

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Transmission mounts and engine mounts are only for better shifting. Probably the first thing to do... amazing difference.. Research the forum articles for more information.

Front Control Arm Bushings (FCABs) are to help keep the alignment in check. These are OFFSET bushings, similar to the E36M3 and NOT the same as non-M\\\'s. They also provide a little more caster.
Rear Trailing Arm Bushings (RTABs) are for keeping the rear thrust angle in check coming out of a corner under hard acceleration.
FCABs and RTABs are not necessary on a street driven car in all actuality except to massage your own ego. If you need to replace them because they are worn, then go for it.. Aftermarket poly's cost the same or less than OEM.

IMHO Coilovers are also not necessary on a street car unless you want more spring rate. You can get more spring rate (on stock dampers) by going to H&R's or Eibach's springs. I personally would stay away from the Eibach's. H&R's are a better product...
A good upgrade, that will not require a new alignment is replacing your rear damper (shock) mounts. I personally like the Rogue Engineering mounts. They give a firmer feel and help the rear dampers stay in control instead of wondering around the upper pivot point.

As part of your yearly (or more) maintenance checks, check the rubber on the front upper and rear upper damper mounts. The OEM's will crack with age and require replacement.

As Pal states, a good non-factory alignment will do wonders. You can pull the two (hex head) alignment pins (used for installation at time of manufacture) and you can get a little more camber. If you need more camber, a E36 camber kit (shims or washers and longer bolts) will get you up to -3.5' of camber. I personally would not go above -2.5' for relatively even tire wear across the face of the tire. I run -2.5 in the front and have pretty even tire wear.
Rear camber depends.... some cars get more than others. I personally have -2.1 in the rear and that is all I can get. Adjustable camber arms fix this but the entire differential has to be dropped to get them installed.
The E36 camber kits will NOT work on non-M\\\ cars. Different damper mounting.

On the MC, a strut bar will do you NO GOOD on the street, and get you very little on the track. It does add 'bling' to the engine compartment....

You can also replace the front and rear anti-roll bar bushings with PowerFlex units.

In case you have not done to much research on your MC, I would HIGHLY advise on having an oil analysis performed at each oil change. The S54 is susceptible to rod bearing wear and eventual failure if not caught early. Replacement of the rod bearings is not too costly.
 

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Discussion Starter #14
Very useful info.
I'm not a novice when it comes to setting up cars - I've been building my own race cars for the last 40 years - but each one is different, and you can save a lot of time by finding out what works and what isn't necessary from people that have the experience!

I wound up with -2.0F and -1.7R on the Solstice (the car I most recently set up) having to use a bit of trial and error as all the guys into handling on those cars are doing solo events which call for different settings than I wanted (less front roll stiffness, for example).

The BMW seems to have better handling than the Solstice did in stock form - not many manufacturers get it right for enthusiasts, they usually set things too soft to please the timid drivers. Maybe no timid drivers bought M cars?
 

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How do you go about getting an oil analysis? I am about to change the oil on my Z4MR as I store the car for the winter and would be interested in seeing what information can be gleamed from the used oil. Thanks.
 

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Blackstone-labs for oil analysis.
 
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