BMW Z4 M Coupe, Z4 MC, Z4M, StopTech, ESS Tuning

MyMCoupe.com a site dedicated to Scatha, a 2007 BMW Z4 ///M Coupe
Power Chassis	Brakes and Wheels Exterior	Interior Gallery

Brake and Wheel Mods

     Wheels and brakes are some of the best places to shed weight from a car. Reductions in rotational unsprung mass is considerably more effective than mass taken from non-rotational sprung areas.
     The stock BMW Z4 M's brakes are very good, even for occasional track use. But for heavy tracking the car needs more cooling capacity. Enter StopTech. Their rotors cool better than any other aftermarket rotor (that's why the Viper got its Brembo rotors replaced with StopTechs for the ACR track version!), and their calipers are the stiffest you can buy.
     I run R-comps on the street - yes, even in the rain. But my M Coupe isn't my commuter car. The RA-1 and NT-01 are both excellent tires. I get around 5000 miles + 10 to 12 track days out of a set of R-Comps. The track kills them faster than the street, but even so they last a lot longer than summer performance street tires would in the same conditions.

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Mod # 48, Nitto-NT01s

Speed Ventures and many other reputable sources have been praising the NT-01 for some time now. As I used up my second set of RA-1s I decided to try something new. Also, at the time I ordered mine, anyone who ordered a set of Nittos through America's Tire or Discount Tire Direct got an $80 coupon towards a Speed Ventures track event (email Aaron for current details)! Given that the NT-01 is about $100/tire less expensive than the RA-1, the decision is a no-brainer. Like the RA-1s before them, I run 245/40R18 NT-01s front and 275/35R18 NT-01s rear. The Nittos are great on the street and track, like the Toyos, and make similar noise once heat cycled. The NT-01s drop 3lbs compared to the RA-1s.

M$RP: Install Time: Mass effect: Vendor:	$919 1:00 -3.0lbs DiscountTireDir

Mod # 32, Brake Duct Cutouts

This is a simple mod that allows more air to cool the front rotors. Simply cut out the BMW duct plugs. Below you can see how much more air gets let in. The air isn't ducted directly to the rotor as would be ideal, but the high pressure cold air will blow out hot air otherwise trapped inside the fender, and if the steering wheel is turned the air will blow directly on one of the rotors.

M$RP: Install Time: Mass effect: Vendor:	$0 0:20 -0.20lbs BMS

Mod # 27, Wheel Stud Conversion

This was necessitated when I had to add spacers (see mod # 26) so my BBS RG-Rs would clear the large StopTech BBK calipers. Studs are also stronger than lug bolts, which is good for a car that sees a lot of track time. I don't have a good picture of the studs.

M$RP: Install Time: Mass effect: Vendor:	$150 0:30 0.44lbs BMS

Mod # 26, StopTech 4-Wheel Big Brake Kit and H&R Spacers

     StopTech makes great brakes. I am a strong believer in their philosophy of a balanced brake system. Brembo makes good quality products, but in my opinion do not fully optimize their brake system's balance. Also I have been witness to several occurrences in which Race Technologies, Brembo's North American sales arm, has publicly misrepresented the physics of braking and even gone so far as to slander other brake manufacturers. Rotora has done the same and is also not to be trusted. There is a lot of bad blood between certain aftermarket brake manufacturers, and I have no intention of becoming involved in mud slinging. My opinions are formed from firsthand experience and is shared only to provide consumer protection to the BMW community.
      I know nothing bad about Alcon, Power Slot or Wilwood, aside from their lower price points necessitating a decrease in overall quality. I've run Baer brakes before on my '66 Mustang and I liked them a lot.
      My M Coupe was the test mule for StopTech's Z4 M 4 wheel BBK. It is comprised of components from their E46 line, but with some altering of brake torque to balance the system for the Z4 M. These brakes are great on track, and with street pads make no noise in daily driving. On the track I've played around with different pads, but tend to run Hawk HT-14s. On the street I use the Axis pads that come with the StopTech kit.
      I needed 15mm H&R spacers on my front hubs for my BBS RG-Rs to clear StopTech's 4-piston calipers. With other wheels, or other offsets, spacers may not be needed. StopTech's 4 wheel BBK will fit behind BMW's Z4 M wheels, although clearance is very tight.
     At first glance it appears that very little weight was shed by StopTech's BBK. However this is due to the much larger StopTech rear rotors needed to balance brake torque and increase cooling. The StopTech BBK trims significant weight off the front, and adds only a few pounds in the rear. The H&R spacers add another few pounds. Overall there is a sizeable weight shift rearward, which makes the handling balance of the Z4 M even better.

M$RP: Install Time: Mass effect: Vendor:	$6000 3:00 -5.70lbs StopTech

Mod # 18, BBS RG-Rs and Toyo RA-1s

     It's no secret that I'm a fan of BBS wheels. I have BBS RS-GTs on my E39 M5, and BBS RG-Rs on my 540iT. There are other quality lightweight wheels out there, but I chose the BBS RG-Rs in Diamond Black for my M Coupe because of their strength, weight and appearance.
     I chose the Toyo RA-1 because of recommendations from trusted sources. It's a great tire and I am very satisfied with its performance on street and track. It is a loud tire, compared to street tires, but no louder than other R Comps. I now run Nitto NT-01s, see Mod # 48.
     Here are pictures of my M Coupe right after the RG-Rs and RA-1s were installed. Note the horrible ride height of the stock suspension!

M$RP: Install Time: Mass effect: Vendor:	$3700 1:00 -16.00lbs BMS