[tetsuo111]

Anyone have the Cliff Notes on brake upgrades? I’ve read so many threads about 135i, 335i, F30, CTS-V, blah blah blah. My understanding is that 335i has the largest calipers and rotors with PNP fitment. Is this the way to go?

The goal is large rotors compatible with 17" ARC-8 rims for shorter stopping, and a design to mitigate heat-induced fade. There are plans for ducts in the queue.

It looks like a very few are using Euro-spec E34 M5 rotors and in some cases the matching OEM calipers. The rotors are 345 x 32, so 3mm smaller diameter and 2mm thicker compared with 335i rotors. I looked into these further and it just makes me cry when comparing these to the crap on the new cars.

The E34 brakes are designed like race parts. Not a Brembo decal to be seen. Downside? Expensive at $658/pr. I can buy Girodisc rotors for $800. Wonder if the stock 335i calipers would work with these…..

https://www.ecstuning.com/ES2610308/

[feuer]

No, different rotor offset (height)

[tetsuo111]

Originally Posted by feuer

No, different rotor offset (height)

Thanks, Feuer. Was hoping to hear from you.

Guess I'll keep it simple and go with the Girodisc 335i-spec rotors.

Can you suggest a motorsport caliper for this app? Prefer something sourced from AP, Alcon or PFC. Fixed. Light is good. Don't care about number of pistons, just need to know total piston area to engineer the hydraulics. Most of those calipers are made for lighter cars (duh) and smaller rotors.

[feuer]

Originally Posted by tetsuo111

Thanks, Feuer. Was hoping to hear from you.

Guess I'll keep it simple and go with the Girodisc 335i-spec rotors.

Can you suggest a motorsport caliper for this app? Prefer something sourced from AP, Alcon or PFC. Fixed. Light is good. Don't care about number of pistons, just need to know total piston area to engineer the hydraulics. Most of those calipers are made for lighter cars (duh) and smaller rotors.

The most affordable if you want 17" would be the stock f30 335i 340mm front brakes. Then 355mm Stop Tech for 17" Then for 18" wheels MPerformance f30 335i 370mm, 380mm Stop Tech, 370mm AP R1.

[tetsuo111]

Originally Posted by feuer

The most affordable if you want 17" would be the stock f30 335i 340mm front brakes. Then 355mm Stop Tech for 17" Then for 18" wheels MPerformance f30 335i 370mm, 380mm Stop Tech, 370mm AP R1.

I searched first and often but never did find the piston size on those F30 340mm calipers. I need to confirm balance and compatibility with the MC. Well, it's known they are NOT compatible with the E90 non-M MC, so I assume the piston area is more than 57 mm^2. I picked-up an M3 MC just to get some brake feel, but haven't installed yet.

Objective data-driven question - is the F30 340mm caliper compatible with the larger 335i 348mm rotor? 8mm difference in diameter. Has been impossible to get tech specs on those calipers.

Subjective opinion question - does the fixed F30 caliper benefits outweigh the F30 340mm smaller rotor size compared with the stock 335i 348x30 rotors? I suppose either would be a significant upgrade in thermal capacity and stopping distance compared to stock 328i 312x24mm rotors.

[feuer]

Originally Posted by tetsuo111

I searched first and often but never did find the piston size on those F30 340mm calipers. I need to confirm balance and compatibility with the MC. Well, it's known they are NOT compatible with the E90 non-M MC, so I assume the piston area is more than 57 mm^2. I picked-up an M3 MC just to get some brake feel, but haven't installed yet.

Objective data-driven question - is the F30 340mm caliper compatible with the larger 335i 348mm rotor? 8mm difference in diameter. Has been impossible to get tech specs on those calipers.

Subjective opinion question - does the fixed F30 caliper benefits outweigh the F30 340mm smaller rotor size compared with the stock 335i 348x30 rotors? I suppose either would be a significant upgrade in thermal capacity and stopping distance compared to stock 328i 312x24mm rotors.

I have posted the info on the f30 caliper piston size and will try to dig it out (on my cellphone now sorry) but they are all the same, meaning for the 340mm and 370/380mm rotors. Yes, you can mount f30 335i caliper with e90 335i but pads will not cover the whole rotor sweep pad area. The f30 are superior on oher aspects as well. They are lighter, easier to change pads, equal outside-inside pad and rotor wear, less prone to vibrations and prettier to look at.

[tetsuo111]

feuer Thanks again for the info and your patience. The F30 being PNP is attractive.

If you can find the piston sizes, I'll say thanks again! I've been searching but nothing yet.

[Ruddigger]

I'll just sit back and let you do all the legwork, then copy whatever you end up with.