Z4 Coupe (E86) Z4M Brake Upgrade

Just put in to get front Racing Brake rotors and their front Performance Upgrade calipers!

I've been on the fence for a long time about upgrading to a BBK. But Racing Brake's deal for front rotors and performance upgrade calipers, as well as shortly to be released rear version of the rotors and performance upgrade calipers (with E brake) just pushed me over the edge. Well worth a look if you're on the fence like I was about a BBK or just in need of new rotors.

Rotor upgrade is to a slotted thicker rotor (30mm vs. 28), which has replaceable rotor rings and re-useable hats. More heat capacity and longer life (2mm wear limit vs. 1.6mm OEM). Calipers are aluminum 4 piston with 40mm/44mm pistons (same as typical Brembo and Stoptech piston sizes for E46 M3 BBK). There's more wheel clearance (5-6MM) with these calipers too, which gives more flexibility. Built in seals (vs. dust boots) and along with stainless (vs. aluminum), which probably adds up to better durability for track use.

Once I have all 4 corners done I really won't miss hassle of street -> track -> street pad swaps with stock calipers. Not the end of the world, but it does take time that I'd rather spend on other things.

Will post pics when shipped and installed.

EDIT: Link added to top of post.

Why?

Originally Posted by Pinecone

Why?

Why not?

But seriously, my front rotors are worn out of spec, and I need new ones. So I was looking at other options besides OEM (or similar, like Turner), and sizing up options/value.

RB is a good deal with the 20% discount right now, and it makes the cost competitive to OEM with several pluses. The RB has 2mm of additional rotor thickness and an allowable 2mm wear factor (factory is only 1.6mm). RB is a bit more than OEM, but hats are reusable with replaceable rotor rings. The RBs have 25% greater wear capacity, are slotted not drilled, and reported to be harder (denser). Several folks heavily tracking their cars report these wear much more slowly that OEM. So actual durability may be higher than just the 25% great wear factor. So, why not get more for my money rather than going OEM?

As for the PU upgrade, there are several reasons. First, because it should have a better pedal feel. Second, swapping pads (street -> track -> street) with the stock calipers is a total PITA and it's getting old. Swapping pads with the PU calipers is a piece of cake. Third, I can't lie that about the fact that they just look damn cool. (Yes, appearance!) Fourth, the rear PU upgrade (and RB rotor, with same pluses, and I'm close to needing rear rotors too) will really make swapping pads on all 4 wheels a breeze. With 4 piston calipers on all 4 wheels pedal feel should improve, and then there's that "appearance" thing again. Lastly, there's an upgrade path to E9x M3 rotors--just need new rotor rings and different caliper mounting bracket. I think that's overkill, but it's still nice to have options.

I look forward to some pics, Finn

OK, just asking. You seem to have actually thought about it and made sure you knew what it is about.

Not everyone does.

Originally Posted by Pinecone

OK, just asking. You seem to have actually thought about it and made sure you knew what it is about.

Not everyone does.

Yeah, thought through it a bit. Sometimes too much! Occupational hazard I think (analysis based line of work).

It's a pretty good deal, with the 20% discount (which is good on the GB through 10/15) even on the rotors only, and especially if the car sees some track use. (Mine does.) Stock brakes on the ///M are really damn good, but I'm really hoping to regain the pedal feel and ease of pad swaps I had with my STI.