Brembo BBK 380mm 4pistons, possible to convert into 355mm?

[Gt4]

I have an older Brembo BBK in 380mm. They are 4 pistons. Those kits were offered for E46 M3 back in the days as well as 6-pistons and 8-pistons. These days I think they only offers 6-pistons option in 380mm.

I think they are called the F50 front calipers and Lotus rear calipers. Will take pics and get number on calipers soon.

My question is: it is possible to buy brackets from Brembo to convert them into 355mm front & rear? And can I buy 355mm rotors and keep my actual hats?

Would prefer to go smaller to be able to run any 18’’ wheels on track.

And one more question: do Performance Friction offer a track pads option for those calipers like Compound 11?

[Gt4]

The 2 part cast calipers part number are the following:

Front: 20.7678.00 & 20.7679.00
Rear: 6971 & 6972

[bigjae46]

I have a 380mm/ST60 Stoptech BBK on my E90. I explored converting it to a 355mm rotor so I can run 17s. At least with the Stoptechs which I don't think are too different from the Brembo's...the rotor hat bolt diameter is different so you have the buy the entire assembly.

At that point, with the bracket cost, its not much cheaper than buying a new BBK. But this was a few years ago. Not sure what prices are doing now.

[Gt4]

yeah I am also considering selling and buying a brand new Brembo GT-S kit front and rear due to Brembo spare parts cost

[r4dr]

You would need new hats, rings, brackets and possibly brake lines. Find a friendly Brembo dealer and give them the original kit part #. They should be able to quote you parts from that kit.

I helped someone with the same oddball 380mm 4pot kit price it out. It’s been a while, but I recall it wasn’t really worth it.

[bmw m3 s50]

You would need new hats, rings, brackets and possibly brake lines. Find a friendly Brembo dealer and give them the original kit part #. They should be able to quote you parts from that kit.

I helped someone with the same oddball 380mm 4pot kit price it out. It’s been a while, but I recall it wasn’t really worth it.

As mentioned, you will need all of this to work. The brackets/carriers will be impossible to find used, so you will need to buy new from Brembo. You could get away with reusing the brake lines. Zeckhausen sells 355mmx32mm Rotor rings that are made by Stoptech that will fit Brembo BBK kits. They did also sell replacement rotor hats a few years ago but not sure if they discontinued them.

Essentially, you using only the calipers and scaping everything else. Honestly, your better off selling the 380mm BBK and buying a 355mm kit used.

[Sharocks]

I just priced out brackets a while ago. I have a spare set of Brembo F50 calipers.

LOL

$880 bucks for a pair straight from Brembo. Does not include shipping.

It would be easier for you to sell the fronts and get a front kit you want.

[Gt4]

I just priced out brackets a while ago. I have a spare set of Brembo F50 calipers.

LOL

$880 bucks for a pair straight from Brembo. Does not include shipping.

It would be easier for you to sell the fronts and get a front kit you want.

Wow that’s crazy for a pair of brackets…

If I don’t sell my kit, I will ask my machinist to make custom front & rear brackets for 355/345mm rotors

That way, I will o ly buy rotors and pads for track