Front Brake Upgrade
- Thread starter Boltz
- Start date
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Anonymous
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The 18i /20i has 300mm discs the 28i has 330mm discs..
I did this you need the discs and the calipers AUTODOC does them all at reasonable prices...straight bolt on..plus new disc backing plates
Have to say at subsonic speeds didn’t feel any difference but heh, looks better with thin spoke wheels
I did this you need the discs and the calipers AUTODOC does them all at reasonable prices...straight bolt on..plus new disc backing plates
Have to say at subsonic speeds didn’t feel any difference but heh, looks better with thin spoke wheels
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Anonymous
Guest
Yes same thoughts crossed my mind, another E89 28i Forum chap has swapped his discs n calipers for 6 potters so I had his..the calipers were all corroded so did a trade in with autodoc to get refurb units.. 
Anyway as I said can’t really tell the difference afaik no one has complained on the N20 variants about bring under braked anyway...the chap said his 6 pot replacements were not obviously better, but he does track day his car.. :tumbleweed:
The 330mm discs n calipers won’t allow some 17 bmw wheels to fit..103s don’t ....I found out the hard way.. :headbang:
Anyway as I said can’t really tell the difference afaik no one has complained on the N20 variants about bring under braked anyway...the chap said his 6 pot replacements were not obviously better, but he does track day his car.. :tumbleweed:
The 330mm discs n calipers won’t allow some 17 bmw wheels to fit..103s don’t ....I found out the hard way.. :headbang:
Just fit these pads Ferodo ds2500
Guy at my local Indy races BMW, i was asking about calipers/discs/slotted/drilled blah blah blah.
He said for road use all you will ever need is the Ferodo pads.
Have had this advice echoed by several in the industry so when mine wear down I will be popping a set in
Guy at my local Indy races BMW, i was asking about calipers/discs/slotted/drilled blah blah blah.
He said for road use all you will ever need is the Ferodo pads.
Have had this advice echoed by several in the industry so when mine wear down I will be popping a set in
Have you thought about putting four pot calipers and 370mm discs from a 340/440i on it? The calipers are on 40i models as well as M3/M4's and were a substantial upgrade over the standard discs on my Z4 35i. Should be a big improvement for a 18i and will bolt right on.
May want to consider upgrading the rear discs to those from a 35i/is though as there might be a big bias difference otherwise.
May want to consider upgrading the rear discs to those from a 35i/is though as there might be a big bias difference otherwise.
Boltz said:
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!
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Anonymous
Guest
If I may interject at the risk of yet another flame war...
Around £200 gets you all parts for the 28i except pads and if you want to spend £100 ish on Ferodos.. source autodoc
The 20i/28i seem more than adequately braked with the 330mm discs
Like 19 wheels over similar 18 or 17 wheels adding much heavier rotors and calipers adds unnecessarily to unsprung weight...
The 18i is 100kg lighter than a 35i so again less mass
As I said, anecdotally, a chap swapped his 28i brakes for a 6 pot BBK and his perception as a fairly hard charging person was that there was little improvement in his experience..
Of course no one can deny that these BBK look pretty so if that’s what floats your boat it’s fine..
Around £200 gets you all parts for the 28i except pads and if you want to spend £100 ish on Ferodos.. source autodoc
The 20i/28i seem more than adequately braked with the 330mm discs
Like 19 wheels over similar 18 or 17 wheels adding much heavier rotors and calipers adds unnecessarily to unsprung weight...
The 18i is 100kg lighter than a 35i so again less mass
As I said, anecdotally, a chap swapped his 28i brakes for a 6 pot BBK and his perception as a fairly hard charging person was that there was little improvement in his experience..
Of course no one can deny that these BBK look pretty so if that’s what floats your boat it’s fine..
When I look on autodoc there is quite a selection, from Viaco @ 32.75 to Bosch @ 131.35. There are Zimmerman Sport ones that are carbon coated and perforated @ 86.84....is there advice as to which ones to go for? Presuming also then it would be sensible to stick to the same brand for all parts except the pads? The zimmerman ones look quite grey as opposed to the shiny ones currently I have...will they turn shiny or would they always look different...any experience much appreciated!
Thanks.
Thanks.
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Anonymous
Guest
That's the issue with Autodoc, choice is often the major issue..looking at the options, personally I would (now) go with the Ferodo discs, several forum members suggest if you are a more spirited driver that there fast street pads are used, McButler amongst others is a protagonist for these, I'm running the OEM discs with Brembo pads and TRW calipers
Slotted and or drilled are flattery type cosmetic for street use and remove mass and weaken the structure compared to the same size disc whole IMHO. :tumbleweed:
Unlike the E85s where some seemed to be underbraked I've not experienced that wiltimg/saging feeling, well at least not on the brakes! :rofl:
Slotted and or drilled are flattery type cosmetic for street use and remove mass and weaken the structure compared to the same size disc whole IMHO. :tumbleweed:
Unlike the E85s where some seemed to be underbraked I've not experienced that wiltimg/saging feeling, well at least not on the brakes! :rofl:
Haha I'm getting on, so brake fade isnt my immediate issue....if I could just get over my current obsession with upgrades and car parts! Thanks for advice...why would you select them by the way, value for money as there's no need to spend more or you know the quality is good or better?
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Anonymous
Guest
Its tough when there are several options, and different people wax so lyrically and strongly about their choices and opinions..
Ferodo have been in the braking business for ever and I've never heard someone say that ferodo brakes are crap.
Its only a relatively low tech disc at the end of the day
I used autodoc drilled front Brembos on my Volvo XC70 and it feels marginal at times..so the holes don't sound great to me..
I heard some warnings about Febi Bilstein parts but the two engine bits I did buy were actually BMW OEM with the BMW logo ground off.
So lucky dip..
Ferodo have been in the braking business for ever and I've never heard someone say that ferodo brakes are crap.
Its only a relatively low tech disc at the end of the day
I used autodoc drilled front Brembos on my Volvo XC70 and it feels marginal at times..so the holes don't sound great to me..
I heard some warnings about Febi Bilstein parts but the two engine bits I did buy were actually BMW OEM with the BMW logo ground off.
So lucky dip..
A
Anonymous
Guest
BeemerGuy said:
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
