[Nenad4884]

Originally Posted by Unspec

Approximately 4mm in spacers was required for the front caliper. Without them, the calipers side too far in the wheel well and aren't centered on the rotor.

Thank you mate 👍

[addy27]

Originally Posted by Nenad4884

Thank you mate 👍

Either the 4mm spacers or you buy the RR4 Ghost or Alpina B5/6 Edition 50 rotors.. Cheaper route is the spacers.

[Nenad4884]

Originally Posted by addy27

Either the 4mm spacers or you buy the RR4 Ghost or Alpina B5/6 Edition 50 rotors.. Cheaper route is the spacers.

Hi, i did buy spacers, just waiting now on rotors od M5 rear brakes. Than i have everything i need and can retrofit 😊

[Nenad4884]

So, i finally try how everything Looks, didn' tryed with rotors bcs they came today and i have other stuff to do..

But, spacer need to be cut appart for ( Look at the pic), need to cut some metal from rotor shield bcs of big calipers.

Need to change wheelbearings, they aren't Bad but i don't wanna any surprises later.

Planning to do this retrofit sometime next week.

[Blue Angel]

Originally Posted by Unspec

Rears off a G series are not bolt on...

Can you check if the G caliper will work with the F bracket? This could open up some options since the F M5/550 rear calipers can be hard to come by.

[Nenad4884]

Originally Posted by Blue Angel

Can you check if the G caliper will work with the F bracket? This could open up some options since the F M5/550 rear calipers can be hard to come by.

Unfortunally, G series calipers don't fit.

[addy27]

Wait, that caliper says 374, meaning the rotor you got is also 374 right? not 395??

[Unspec]

Originally Posted by Blue Angel

Can you check if the G caliper will work with the F bracket? This could open up some options since the F M5/550 rear calipers can be hard to come by.

Unfortunately, already returned the calipers :/

Originally Posted by Nenad4884

Unfortunally, G series calipers don't fit.

Blue angel was asking if the floating caliper will fit on the fixed carrier.

[Nenad4884]

Originally Posted by Unspec

Unfortunately, already returned the calipers :/

Blue angel was asking if the floating caliper will fit on the fixed carrier.

Thnx, yesterday i was so tired, didn't understand quite complete... Now i See..

I don't Know eather, can try to purchase one with return from G series an try, but it will take some time..

Yes, my Front calipers are for 374mm rotors, the Same ones what Unspec has 👍

[Nenad4884]

Originally Posted by addy27

Wait, that caliper says 374, meaning the rotor you got is also 374 right? not 395??

Right,, they are 374mm, not 395 👍

[Flying_Squad]

Has anybody tried to/know if it’s possible to fit E70 X5M rear discs (385x24mm) with the F10 M5 rear calipers and carrier?

I discussed this with forum member Bozman, who did the E70 front conversion and we don’t think it’s feasible for the rear due to the depth of the hub of these rotors.

Just thought I’d double check on here in case someone has attempted it.

[Bozman52]

Here are the spec sheets I referred to when making that determination. As far as I can tell, the E70 X5M rear rotor is near identical to the 550/750 rear, aside from the fact that the rotor surface will sit 9.4mm inboard of the stock rotor placement (78.5mm vs 69.1mm from rotor hat to backside of rotor). I've not tried to physically fit this setup on a car, but at face value, that kind of offsent delta in that direction seems like something that can't be overcome.

[Flying_Squad]

Thanks for providing the diagrams Bozman.

If anyone can definitely rule this option out that would great.

[Unspec]

Any reason you would even need 385's on the rear? That seems like excessive unsprung rotational weight for not much gain, given it's the rear brakes on a front engined vehicle.

[Flying_Squad]

Impossible to find cross drilled F01 370mm rear discs here in the UK/Europe. Wanting to match the cross drilled E70 395mm up front. Already have the M5 Rear caliper and carrier, hence the query.

[addy27]

Originally Posted by Flying_Squad

Impossible to find cross drilled F01 370mm rear discs here in the UK/Europe. Wanting to match the cross drilled E70 395mm up front. Already have the M5 Rear caliper and carrier, hence the query.

if you already have the M5 rear caliper and carrier, then just slap on the 370mm disc and be done.

Regarding matching, Benz has been running drilled rotors up front and plain in the rear for ages. If you really need to match, check out Brakenetic, they could do it and it would be a hefty penny..

And sure, I'll rule out the 385 for you for exactly the same reason as Bozman mentioned. The whole caliper/carrier design is different on the X5m and no one makes an adapter to fit those rotors.

[DT_10]

Hey guys, new to the forum here. Just purchased a new to me 14 550i, and Im looking to do the G series front upgrade (374mm), I just sourced some calipers.

One thing I havent seen discussed a ton is brake bias. Have any of you veterans done those calculations based on piston size / know what the difference is ? That would be the only real reason I would want to upgrade my rears, to keep the bias as close to stock as possible.

Cheers.

[Blue Angel]

DT_10, are you reading my freaking mind?!? I literally just made that spreadsheet last night! WTF man, lol

I'll share shortly, but suffice to say there's not much difference in braking torque between any setup in the front from the F10 528, 535, 550 or F01/G11 750. There's a slight benefit to the F01 rear 370mm setup.

If anyone knows the piston sizes for the X5M front calipers I'd love to add them to the mix!

EDIT: Bozman52, care to look at the markings on your front calipers? If you can't see them on the car, maybe you have pics showing them? Example:

G11 front calipers: 4x40-44/374/36 means 40 and 44mm pistons, 374x36mm rotor.

[Flying_Squad]

Originally Posted by addy27

if you already have the M5 rear caliper and carrier, then just slap on the 370mm disc and be done.

Regarding matching, Benz has been running drilled rotors up front and plain in the rear for ages. If you really need to match, check out Brakenetic, they could do it and it would be a hefty penny..

And sure, I'll rule out the 385 for you for exactly the same reason as Bozman mentioned. The whole caliper/carrier design is different on the X5m and no one makes an adapter to fit those rotors.

How funny, I was using the exact same example when discussing with Bozman re Benz’s approach of plain rears with drilled fronts. I am able to source dimpled F01 rears so will settle for that.

[addy27]

One thing im unable to locate is the spec sheet for the E60 M5 rear brakes (which are also 370x24) but the hat geometry is what I dont know of, or the width of the face that contacts the brake pads. Zimmerman might have it but no one else shows the dimensions (Since brembo it seems did not make them for BMW, VNE did)

UPDATE: Yeah those won't fit either and neither would the E65 ones:
https://shop.peninsulabm.com/product...e-rear-e65-e66

[Blue Angel]

Here you go. I don't have time to explain everything right now, other than there are assumptions made to keep the playing field equal:

[Blue Angel]

DT_10, if you go with the F01 760 rotors + G11 calipers in front your braking torque will increase by (392/381)= 3% and your balance will shift from 64/36 to 65/35. Total braking torque will increase by (605/593)= 2%

This assumes the same brake pad coefficient of friction front and rear.

Four piston G11 calipers have slightly less effective piston area (40mm+44mm) than the single piston (60mm) calipers used on F10 and F01 models. It's only a 1.8% decrease, but it diminishes the 4.8% increase in rotor effective diameter.