BMW M3 E46 - Project Cars - European Car Magazine

0703_ec_03z+bmw_m3+front_view   |   BMW M3 E46 - StopTech Brake Upgrade

Ever play Cars? Although there are no real guidelines, playing Cars has a few unspoken rules.

Rule one: The closer your face is to the floor, the better everything looks.

Rule two: Cool cars must be parked close to each other.

Rule three: Make sure the sound you make matches your car (a 396 Chevelle doesn't go "Zingzzzzingzingzning" like a Honda).

0703_ec_01z+BBS_RGR+modular_wheels   |   BMW M3 E46 - StopTech Brake Upgrade

We are still playing with cars. And although they're a bit larger, we still follow unspoken rules. Perhaps the most sacred rule is: Don't fix something that's not broken.

Project M3 has been host to a few well-placed modifications that have made big improvements. The most visible changes are the 19-inch BBS RGR modular wheels. Light and strong, the RGRs and Toyo T1-S rubber (235/40 and 265/35) have considerably sharpened the handling and response. At first I resisted going from 18- to 19-inch wheels, worried the ride would deteriorate into a teeth-rattling experience. I was wrong. The combination of the new running gear and the Koni adjustable sport shocks and struts have proven to be an awesome set-up. In my opinion, this is the way the BMW should feel.

0703_ec_07z+stoptech+brake_system   |   A few well placed mods and our M3 feels like a different animal. It helps to start with a good breed.

The M3 had good brakes. The front rotors measure 12.8 inches and the rears are 12.9. Tied into dual-circuit ABS and DSC, they rarely felt wanting. So why fix them by swapping in a StopTech system?

The answer played out one recent Tuesday afternoon. The editor of a sister publication (he will remain nameless for fear of reader reprisals... we'll call him Jason Mulroney to protect the innocent) purchased an E46 M3 just like mine. Like me, he loves to drive it daily and searches for places to test its capabilities.

In addition to the zero to 60 mph testing, I thought we'd analyze more dynamic parameters. Mulroney followed me through the Streets of Willow circuit, mirroring my lines and braking points. Although both cars make within 5 hp of each other, my car tended to pull ahead, especially on the long uphill straight. I can only think the reduction in unsprung weight played a part here, as both cars have completely stock engines. Into the first series of turns, it was obvious Mulroney's car lacked the grip. His was fitted with older Bridgestone S0-3s, while mine wore the grippy Toyos.

0703_ec_02z+stoptech+brake_system   |   BMW M3 E46 - StopTech Brake Upgrade

Although drifting is popular with his readers, it's not the ideal way to produce fast laps. Yes, he was having a blast powersliding through the corners, but I was pulling far ahead, which in effect screwed my testing methodology. The second session was more serious and although Mulroney's M3 couldn't maintain my cornering speeds (tire-related), he was doing an admirable job. Around the ninth or tenth lap of the 1.2-mile course, he could not maintain my corner entry speeds. His brakes weren't gone, but they were really hot and unable to shed heat like the big StopTechs.

0703_ec_04z+bmw_m3+side_view   |   BMW M3 E46 - StopTech Brake Upgrade

This is where big brakes really prove their worth: no matter what anyone says, a well-engineered big brake system will out-perform a stock system over time. Yes, pad choice can make a significant difference, but ultimately, pads compromise one area to excel in another. StopTech uses a moderately aggressive street pad that gets up to optimal temperature in a fairly brief period. Former ec tech-geek, Dan Barnes, now StopTech engineering rep, described the pads this way:

0703_ec_06z+bmw_m3+left_rear_view   |   BMW M3 E46 - StopTech Brake Upgrade

"The standard pad we ship with kits is the Axxis ULT. It is a high performance street pad with good initial bite, modulation and release. It has a higher maximum operating temperature than most OE pads, but is not recommended for powerful cars to do extended lapping sessions on the track. The ST-40 caliper uses an FMSI #D372 pad shape, which was once used as original equipment on a popular performance car and is available from most brake pad manufacturers. We carry 19 different performance street and race pads for the caliper from eight different manufacturers and there are many more we don't carry."

But it's not just their track performance that makes StopTech brakes so good. It's also pedal feel and their modulated response, the linear way pedal force translates into braking force. Simply put, the StopTechs feel better than the factory system. They feel more connected and visceral.

0703_ec_05z+bmw_m3+supercharger   |   Our buds at VF Engineering have just finalized the software for an M3 supercharger system. Looks like those big brakes will be put to good use.

In any case, I'm pleased with Project M3. I'm becoming more comfortable with its capabilities and am ready to take it to the next level.

OK, I lied. Two months ago I mentioned Project M3 was being fitted with a supercharger. The truth is, I wussed out and cancelled the install. I feared changing the M3's character would kill it. During the 2006 SEMA show in Las Vegas, I queried every single person I met-even complete strangers-if they'd like a supercharged M3. Everyone, including the polyester jumpsuit-clad guy playing the nickel slots, said yes. And then there are guys like Aaron Neumann, guys I respect who say it's a solid idea. And even if it doesn't work out, the supercharger system (and everything else for this matter) is easily reversible. That's the beauty of bolt-on performance parts.