Front Brake Upgrade

[BeemerGuy]

Also what is the difference between a 1 piston and a floating caliper? Do either work just as well? Is there a big benefit in going aluminium?

Thanks agsin

Your mixing slightly apples and oranges...

Pedantically there are two types of construct...sliding / floating calipers that has piston or pistons on one side and slides on a pins to push the opposing pad onto the other side of the disc..

Opposed calipers have match pair of piston or pistons on both sides of the disc and use both sides to clamp the disc.

There is no intrinsic benefit to an alloy vs steel calipers except a fractional reduction in unstrung weight about 0.5-1kg in 50kg ish of total unsprung weight

Trendy brakes are made out if aluminium in part because it’s much easier to machine than steel plus the ‘sexy’ aspect.

When it comes to pistons you can have any from 1 to 4 pistons on either one side with a floating caliper or 2-8 pistons with opposing action calipers

For street use it’s arguable that a well designed and adequately size single floating caliper and discs provides adequate capabilities

For ‘sexy’ purposes you can fill your boots with as many pistons and size of discs limited only by the caliper to inside wheel rim clearance..

As usual for the manufacturer it’s a cost/performance/marketing trade off..your values may very.

So as previously stated the 20i brake system on the E89 has attracted little criticism for road use...the 28i adds something to an adequate performer

Thanks, appreciated as ever. I thinking although road use only if I remap, the 28i front brake setup would be better/safer...just fairly standard...my trouble is I get carried away with comparing materials, 1 piece, 2 piece etc, different guards, calipers, pads, wear sensors....I think I'd set a budget of 500- 750...but what combo to get off autodoc...and then when I use the app(cheaper apparently) the selection is less (perhaps the rub) as maybe they want to sell these parts first?

 

[Anonymous]

The autodoc app often offers things cheaper than the web page but you can order anything on the app..just put in the relevant part numbers..

Bosch, ATE, TRW, Ferodo are all good suppliers £500 should see it..

 

[Player 1]

Player 1 those brakes look awesome and may I say expensive too so I will just up the brakes to fit in with the 28 spec to which my 18 has now a similar performance

I don't know how much it costs to go the the 28i brakes but for those you'd be looking at roughly £800-£1100 for discs, pads, calipers and small bits such as wear sensor.
Calipers will vary the cost though, There's a good supply available so would depend on whether you want a fully refurbished set that are good as new (£550ish) or something in reasonable working condition (£300ish).

Another option, I do still have the original calipers/discs from my 35i. Would still be a fair upgrade for you, no idea what they're worth though!

What disks and calipers would they have been? 330 x 24 disks internally vented? How old, and are they, and what wear/condition, and are they a straight swap over? I guess I'd need new back plates, pads, sensors, abfguide sleeve kit? Anything else?

The discs are 370x30 discs as fitted to a 340i/440i etc and are indeed internally ventilated. The drilled/grooved ones are an alternative part BMW offer, part number is 34106797603. They aren't left/right sided so easy just to order two.

The calipers are the four piston ones again found on the 340i/440i as well as M2, M3, M4 and more I'm sure. Caliper part numbers are 34116799469 and 34116799470 or 34116875649 and 34116875650. If you're looking for them on ebay however, just search 'BMW 370 calipers' and loads will come up.
Don't confuse them with the similar four piston calipers fitted to the 140i/240i as these only fit smaller discs, not the 370/380mm ones as these do!

The last thing is brake pads, the pads used on a 340i/440i will fit however there is a different compound used in the M cars which will also fit fine. I used the M car pads and they give a really nice solid pedal feel however there's now a 'sport' pad available for the M cars too which I have heard good things about.
Part number for standard pads is 34116878882
Part number for M pads is 34112284969
Part number for Sport M pads is 34112284765

To answer your question on age, the calipers were off of an M4 which I think was 2016 however can't really remember. I repainted them silver, fitted new stainless bleed nipples and added the decals to them.
The discs, pads, retaining clips/pins I used were all new, you'll also need a new wear sensor to fit in the different calipers, again 340i/440i sensors work fine.
I didn't change back plates and am not sure if you actually can, the larger discs come out to meet the edge of the existing plates but don't protrude as can be seen in the below photo. Everything's a dead simple straight swap, it actually took me longer to change the rear pads/discs than it did to swap everything over at the front.

I fitted them in November 2018 and have performed perfectly ever since, I've done roughly 10,000 miles with them now and there's still loads of life left in the pads. They're far more than a cosmetic upgrade and are much stronger than the normal brakes from higher speeds however the better pedal feel alone would also justify it to me having used them for a while.

 

[Player 1]

Do the 28i's have the same brakes as those found on a 35i/is? For keeping costs down, I'd have thought a 35i setup would be a good upgrade for the four cylinder cars if they aren't the same already?

The four piston ones are great however I'd budget around £1000-£1200 to do it properly.
Alternatively if someone want's to go nuts, I've got some six piston M5 calipers sat on the shelf

 

[Anonymous]

Do the 28i's have the same brakes as those found on a 35i/is? For keeping costs down, I'd have thought a 35i setup would be a good upgrade for the four cylinder cars if they aren't the same already?

The four piston ones are great however I'd budget around £1000-£1200 to do it properly.
Alternatively if someone want's to go nuts, I've got some six piston M5 calipers sat on the shelf

Design wise the 18i 20i 28i have very similar design and structures..the 35i brakes are physically very different although I’ve no personal knowledge of any gotchas involved in that option.

The 20i to 28i route is very simple..new discs, new calipers, replacement wear sensor if required and new back plates for completeness...

Even with that I got caught out as my winter wheels were BMW 103 daisies which are 17” and the 28i discs/calipers would fit but the wheels wouldn’t turn..

My Team Dynamics 17” wheels do fit however...

I think with uk spec 35 brakes you need 18” wheels but not sure about that...

 

[mr wilks]

Do the 28i's have the same brakes as those found on a 35i/is? For keeping costs down, I'd have thought a 35i setup would be a good upgrade for the four cylinder cars if they aren't the same already?

The four piston ones are great however I'd budget around £1000-£1200 to do it properly.
Alternatively if someone want's to go nuts, I've got some six piston M5 calipers sat on the shelf

Design wise the 18i 20i 28i have very similar design and structures..the 35i brakes are physically very different although I’ve no personal knowledge of any gotchas involved in that option.

The 20i to 28i route is very simple..new discs, new calipers, replacement wear sensor if required and new back plates for completeness...

Even with that I got caught out as my winter wheels were BMW 103 daisies which are 17” and the 28i discs/calipers would fit but the wheels wouldn’t turn..

My Team Dynamics 17” wheels do fit however...

I think with uk spec 35 brakes you need 18” wheels but not sure about that...

Odd that 17s wouldn't spin over your 28i brakes :? the 35i did come with 17s from factory on some models as like below on style 290

 

[Anonymous]

Do the 28i's have the same brakes as those found on a 35i/is? For keeping costs down, I'd have thought a 35i setup would be a good upgrade for the four cylinder cars if they aren't the same already?

The four piston ones are great however I'd budget around £1000-£1200 to do it properly.
Alternatively if someone want's to go nuts, I've got some six piston M5 calipers sat on the shelf

Design wise the 18i 20i 28i have very similar design and structures..the 35i brakes are physically very different although I’ve no personal knowledge of any gotchas involved in that option.

The 20i to 28i route is very simple..new discs, new calipers, replacement wear sensor if required and new back plates for completeness...

Even with that I got caught out as my winter wheels were BMW 103 daisies which are 17” and the 28i discs/calipers would fit but the wheels wouldn’t turn..

My Team Dynamics 17” wheels do fit however...

I think with uk spec 35 brakes you need 18” wheels but not sure about that...

Odd that 17s wouldn't spin over your 28i brakes :? the 35i did come with 17s from factory on some models as like below on style 290

The 103 were never an OE fit on the E89s..

AFAIK 103s were on the E85s and they never had 330mm ish discs / calipers

As I say my Team Dynamic 17 pro race 1.2 fit fine with at least 2mm clearance

https://www.demon-tweeks.com/uk/team-dynamics-pro-race-1-2-alloy-wheels-in-black-gloss-set-of-4-2000852/

I can only surmise that the 103s are nice n chunky and their thicker than many others...it was just just an interference fit...

 

[Player 1]

Do the 28i's have the same brakes as those found on a 35i/is? For keeping costs down, I'd have thought a 35i setup would be a good upgrade for the four cylinder cars if they aren't the same already?

The four piston ones are great however I'd budget around £1000-£1200 to do it properly.
Alternatively if someone want's to go nuts, I've got some six piston M5 calipers sat on the shelf

Design wise the 18i 20i 28i have very similar design and structures..the 35i brakes are physically very different although I’ve no personal knowledge of any gotchas involved in that option.

The 20i to 28i route is very simple..new discs, new calipers, replacement wear sensor if required and new back plates for completeness...

Even with that I got caught out as my winter wheels were BMW 103 daisies which are 17” and the 28i discs/calipers would fit but the wheels wouldn’t turn..

My Team Dynamics 17” wheels do fit however...

I think with uk spec 35 brakes you need 18” wheels but not sure about that...

So the standard 35i front discs are 348mm and rears are 324mm and a look on realoem suggests they are indeed only fitted to the 35i and 35is. The wheel carriers are the same throughout so I'd say it's safe to assume one could bolt 35i calipers to a 20i without issue.

I don't know if 17'' wheels were ever offered to a 35i but would be the absolute minimum for a 348mm disc and will depend on the exact wheel whether they'd fit or not. I'd probably suggest 18'' to be safe!

 

[mcbutler]

Unless your tracking the car its overkill, guy at my local indy races BMW, I asked him about upgrading calipers, discs he said "dont waste your money just fit Ferodo ds2500 pads.....
Give them a go before you splash out for unneeded hardware....

 

[BeemerGuy]

Unless your tracking the car its overkill, guy at my local indy races BMW, I asked him about upgrading calipers, discs he said "dont waste your money just fit Ferodo ds2500 pads.....
Give them a go before you splash out for unneeded hardware....

Are those pads for the 300 or the 330 front? Or do you think that means putting them on both rear 270 and front 300 if like me currently I'm stock s20i brakes?

 

[mcbutler]

Unless your tracking the car its overkill, guy at my local indy races BMW, I asked him about upgrading calipers, discs he said "dont waste your money just fit Ferodo ds2500 pads.....
Give them a go before you splash out for unneeded hardware....

Are those pads for the 300 or the 330 front? Or do you think that means putting them on both rear 270 and front 300 if like me currently I'm stock s20i brakes?

On all 4 wheels you NEVER mix pads on a road car

 

[Player 1]

Unless your tracking the car its overkill, guy at my local indy races BMW, I asked him about upgrading calipers, discs he said "dont waste your money just fit Ferodo ds2500 pads.....
Give them a go before you splash out for unneeded hardware....

I've not tried different compound pads on the Z4 however have done on my old Vx220 which has seen plenty of track use.
My opinion is that in changing the pad compound you're changing the operating window to work better at higher temperature, therefore last longer before any fade is noticed and give a better bite when warm. What they didn't do however was make you stop any quicker in optimum conditions.

The larger discs and calipers however, feel noticeably stronger all the time, in any condition and I believe that's what you're paying for.

 

[BeemerGuy]

Unless your tracking the car its overkill, guy at my local indy races BMW, I asked him about upgrading calipers, discs he said "dont waste your money just fit Ferodo ds2500 pads.....
Give them a go before you splash out for unneeded hardware....

Are those pads for the 300 or the 330 front? Or do you think that means putting them on both rear 270 and front 300 if like me currently I'm stock s20i brakes?

On all 4 wheels you NEVER mix pads on a road car

Ok thanks.

So for those Ferido Racing pads all round it would cost approx £350 I guess but I cant see a rear equivalent set..?

Going for the front upgrade with:
Bosch 330 disks
Bosch calipers
Bosch warning contacts wear warning
Ferodo premier eco friction
ABS splash covers
Rear :
Ferodo premier eco friction

The cost for the above at today's autodoc prices is £579

Thoughts?

 

[Anonymous]

Are those pads for the 300 or the 330 front? Or do you think that means putting them on both rear 270 and front 300 if like me currently I'm stock s20i brakes?

On all 4 wheels you NEVER mix pads on a road car

Ok thanks.

So for those Ferido Racing pads all round it would cost approx £350 I guess but I cant see a rear equivalent set..?

Going for the front upgrade with:
Bosch 330 disks
Bosch calipers
Bosch warning contacts wear warning
Ferodo premier eco friction
ABS splash covers
Rear :
Ferodo premier eco friction

The cost for the above at today's autodoc prices is £579

Thoughts?

Seems like a reasonable decision..you can over think over agonise these things..

 

[mcbutler]

Also what is the difference between a 1 piston and a floating caliper? Do either work just as well? Is there a big benefit in going aluminium?

Thanks agsin

Your mixing slightly apples and oranges...

Pedantically there are two types of construct...sliding / floating calipers that has piston or pistons on one side and slides on a pins to push the opposing pad onto the other side of the disc..

Opposed calipers have match pair of piston or pistons on both sides of the disc and use both sides to clamp the disc.

There is no intrinsic benefit to an alloy vs steel calipers except a fractional reduction in unstrung weight about 0.5-1kg in 50kg ish of total unsprung weight
Trendy brakes are made out if aluminium in part because it’s much easier to machine than steel plus the ‘sexy’ aspect.

When it comes to pistons you can have any from 1 to 4 pistons on either one side with a floating caliper or 2-8 pistons with opposing action calipers

For street use it’s arguable that a well designed and adequately size single floating caliper and discs provides adequate capabilities

For ‘sexy’ purposes you can fill your boots with as many pistons and size of discs limited only by the caliper to inside wheel rim clearance..

As usual for the manufacturer it’s a cost/performance/marketing trade off..your values may very.

So as previously stated the 20i brake system on the E89 has attracted little criticism for road use...the 28i adds something to an adequate performer

Aluminium (one of the best metallic heat conductors) calipers also dissipate heat far more effectively than steel (one of the worst metallic heat conductors.
But as phondbar says don't overthink it just do your research. As for drilled discs its really a big no, slotted are far better and no cracking risk, which is why you will hardly ever see them on track cars.
Always puzzled me why muy C63 came with drilled discs when pretty much everyone i asked tells me they are not good for high performance cars driven hard..
I think the price you are paying is brilliant for that whole kit.....

 

[BeemerGuy]

I
Also what is the difference between a 1 piston and a floating caliper? Do either work just as well? Is there a big benefit in going aluminium?

Thanks agsin

Your mixing slightly apples and oranges...

Pedantically there are two types of construct...sliding / floating calipers that has piston or pistons on one side and slides on a pins to push the opposing pad onto the other side of the disc..

Opposed calipers have match pair of piston or pistons on both sides of the disc and use both sides to clamp the disc.

There is no intrinsic benefit to an alloy vs steel calipers except a fractional reduction in unstrung weight about 0.5-1kg in 50kg ish of total unsprung weight
Trendy brakes are made out if aluminium in part because it’s much easier to machine than steel plus the ‘sexy’ aspect.

When it comes to pistons you can have any from 1 to 4 pistons on either one side with a floating caliper or 2-8 pistons with opposing action calipers

For street use it’s arguable that a well designed and adequately size single floating caliper and discs provides adequate capabilities

For ‘sexy’ purposes you can fill your boots with as many pistons and size of discs limited only by the caliper to inside wheel rim clearance..

As usual for the manufacturer it’s a cost/performance/marketing trade off..your values may very.

So as previously stated the 20i brake system on the E89 has attracted little criticism for road use...the 28i adds something to an adequate performer

Aluminium (one of the best metallic heat conductors) calipers also dissipate heat far more effectively than steel (one of the worst metallic heat conductors.
But as phondbar says don't overthink it just do your research. As for drilled discs its really a big no, slotted are far better and no cracking risk, which is why you will hardly ever see them on track cars.
Always puzzled me why muy C63 came with drilled discs when pretty much everyone i asked tells me they are not good for high performance cars driven hard..
I think the price you are paying is brilliant for that whole kit.....

I guess I'd also need new caliper brackets, and guide sleeves and bolts etc, or would the existing parts from.the 300 setup be ok, or do I need all new parts?

When the disk size increases from 300 to 330 does the caliper bracket need to increase in size too?

Do I need to buy new guide sleeves, and brake accessory kits too?

It's hard to work what I to buy as some parts clearly say 330 or 300.....confused.com

 

[Anonymous]

No just buy the bits specified it’s all bolt on using existing remaining parts

 

[BeemerGuy]

No just buy the bits specified it’s all bolt on using existing remaining parts

Ok thanks, that's great...will speak to the garage Monday and see what they will charge, if they're still working and hopefully press on asap. This place is grrrreeeeaaattttt thanks again!

 

[BeemerGuy]

Does anyone know what the "surcharge" is for on Autodoc, or what they call the "core charge" on the, what must be sister site, www.onlinecarparts.co.uk. The seem to just add on another £100 so no apparent reason with no explanation of what it is - any ideas?

 

[R.E92]

It'll be a refund you get when you return the parts you take off your car. If you aren't replacing like for like then you'll probably fall foul of that and not get the core refund.

It's useful on parts like calipers where if you get a seized retaining bolt or stuck piston you can send them the dud part after the work and you get your £100 back as they will refurb your old part and sell it. Not so useful on upgrades.