This upgrade seems to be very common, Im also a commoner and have been thru this.
following are responds I've received from the other bros here:
credits to wt_know:
Hi wt know,
e90/92 335 and e93 335 all use the same brakes correct?
i was contacted by a fellow bro saying he got a e93 stock brake set to let go, but his unsure if its gonna fit onto my e90 320 even if the rear hat is mod.
I see from past threads everybody asking for e90 or e92 335 brakes only. is there e93 335 locally in the first place?
Quote Originally Posted by wt_know
335 brake setup, front rotor = 348mm & rear rotor = 336mm
335 front is direct plug and play for 320
335 rear need to modify the bracket in order for the handbrake to work (cost about$500-$600 for the bracket modification)
you cannot reuse the 320 rotor for 333 caliper as the 320 rotor size is too small.
if you go with the 335, get the front+rear as a complete setup. you can either use the oem 335 rotors or rotora x-drilled/slotted rotors (more expensive). in term of brake pad, i suggest to use oem (perfect fit for caliper, no screeching sound, cheap and good, problem is heavy brake dust)
if you go with bmw performance brake, you can either get the front which is direct fit and leave the rear. else, you can also modify the rear to fit. the modification cost, i forgot how much already. the bmw performance front cost about $2.8k + rear should be $4k++
check out this thread
http://www.bmw-sg.com/forums/member-...-320i-lci.html
my advice
a. if go with 335, get a used set > cheaply > front & rear
b. if go with bmw performance, get front and rear as a complete set
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credits to site sponsors on costings - please verify as these are >1yr old quotes.
To mod the 335 rear disc to fit a 320 is $450. We need to have the rear disc to be machined and requires a couple of days.
Labor to install all 4 brake disc and calipers including partial removal of rear disc plate is $200. We have to do bleeding and replacement of brake fluid for $70 using Motul dot5.1 brake fluid.
the following mods will cost $580 and is only before GST. We flush and bleed the entire braking system with Liqui Moly dot5.1 brake fluid. If you wish to proceed with the following job, I would need you to bring the rear brake disc to us like 3 days in advance to get it modified to fit your rear