M3 single piston caliper brakes, 135i multi piston calipers

[ward]

Originally Posted by ruff

Swamp, I was only responding to Ward's delightful comments with some over zealous statements to try and make a point with him.

a good single piston design can be just as good as a multi pot design

there's many on here who just think the single pots aren't as good because they're not as pretty as the fixed multi pot calipers.

you do know that multi piston calipers can create more heat issues than single pots as the brake line goes over the rotor (which will be HOT if it's being driven hard) while the single pot does not get it's fluid heated in the same fashion as the fluid is only on one side of the rotor.

There are advantages and drawbacks to each design, one design isn't as pretty and that's why most people prefer multi pots.

[consolidated]

The 135i will be BMW's best cost to performance product in a long time, it's going to be a "recruiter" to first time BMW buyers.

Those buyers are younger, potentially driving sport oriented Japanese cars and used to being sold big discs with multi-piston calipers with Brembo and whatever on them. It also seems to work well with Porsche.

Not going with what the market expects here would be a mistake. I'm glad they made this change instead of looking like a stubborn luddite to new buyers.

[footie]

Multi-piston calipers do have a benefit over single piston in that the pressure is better spread over the entire brake pad, but neither caliper or pads are as important as cooling and the best way to promote cooling in any braking system is through the actual disc/rotor itself. The discs on the M3 are cross drilled unlike the 135i which are not, so don't think for one moment that the 135i will stand the same abuse as the M3's will just because of the number of pistons it has.