F31 335i New Brakes

[willttqs]

So my car is approaching 70,000 miles and I think it will be needing new pads / discs shortly in the next 6 - 12 months.


It currently has the grey unpainted calipers on the front and basic callipers on the rear. I wish the original purchaser had specced the brake upgrade when it was bought new!


If I keep the car, I am thinking of getting the m performance brake kit to be fitted on to it. Do you think this is a wise idea? I am also trying to find the best price for them.

Or i could buy the blue callipers on somewhere like eBay, but not to sure about that....

[d_a_n1979]

I think it'd be a straight forward upgrade; you need to find out if you need the carriers also

But I'd guess it'd be calipers, carrier and then obviously, discs & pads

Have you checked BMW to see if they offer this package at all?

[RUSSELLM]

I’m the same. Will probably wait until the front discs need replacing on mine.

I’m after the Red kit, part number 34112450468 https://shop.bmw.co.uk/bmw-uk-responsive/en_GB/p/-...

Rear discs aren’t included in that kit, but I gather they’re the same as the one’s already fitted.

I notice they’re for 18” wheels or larger, which isn’t a problem.

BMW shop lists them at £1950 including front discs. Sytner Coventry have been advertising that kit for £1800, over the last few months.

Edited by RUSSELLM on Monday 5th April 13:10

[willttqs]

Thanks, I’ve seen an orange kit at around the £1800 mark too. I’m not fussed about colour, just want them fitted as cheap as possible.
Cheltenham bmw who are usually cheap quotes £2400 all in!

[anonymous-user]

The upgraded brakes look better but I doubt they will stop the car any quicker. The calipers on the front will be the same for 340mm.
My understanding is bigger discs reduce fade not improve stopping power.

[Pizzaeatingking]

Just buy a set of blue 370mm calipers and get your choice of discs and pads. The calipers are the same in either case.

[RUSSELLM]

Where do you get the callipers from ?

BMW shop is £615 a side for the rears, and £630 a side for the fronts, so £2490 for the lot

[ian332isport]

RJWR said:

My understanding is bigger discs reduce fade not improve stopping power.

Your understanding is not correct.

All other things being equal, larger diameter disks will improve stopping power. The further you can get the braking surface from the centre of the wheel the better.

It’s similar to how using a long breaker bar provides extra leverage to loosen your wheel nuts. It’s way more difficult if you use a short breaker bar. Bigger discs work in the same way.

[320d is all you need]

The 340mm/370mm callipers are physically the same (piston sizes etc) but the calliper mounting holes are in different locations


Either the 340mm or 370mm will be a great upgrade from your standard ones.

Only problem is they are quite pricey - seem to hold their money well.

Around £500 for callipers alone on Ebay. They have a habit of seizing and snapping the bleed nipples too, so I'd budget for a rebuild (and hope you don't need to do it!!)

[Legnum Nick]

ian332isport said:

Your understanding is not correct.

All other things being equal, larger diameter disks will improve stopping power. The further you can get the braking surface from the centre of the wheel the better.

It’s similar to how using a long breaker bar provides extra leverage to loosen your wheel nuts. It’s way more difficult if you use a short breaker bar. Bigger discs work in the same way.

I get the force applied is greater. However once the tyres are at their adhesion limit then bigger brakes can't stop you any faster. Assuming that the smaller brakes are capable of hitting the limit of grip, then I'd agree that brake fade is the main advantage of bigger discs.

[anonymous-user]

Legnum Nick said:

I get the force applied is greater. However once the tyres are at their adhesion limit then bigger brakes can't stop you any faster. Assuming that the smaller brakes are capable of hitting the limit of grip, then I'd agree that brake fade is the main advantage of bigger discs.

The majority of cars will already be able to lock up their wheels. Increasing the brake torque will only exaggerate this affect, so consequently the only noticeable benefit is heat dissipation.

OP you will need to consider suspension and tyre performance in order to improve braking. It is unlikely the stars setup will not be up to your requirements.

[hulksta]

willttqs said:

So my car is approaching 70,000 miles and I think it will be needing new pads / discs shortly in the next 6 - 12 months.


It currently has the grey unpainted calipers on the front and basic callipers on the rear. I wish the original purchaser had specced the brake upgrade when it was bought new!


If I keep the car, I am thinking of getting the m performance brake kit to be fitted on to it. Do you think this is a wise idea? I am also trying to find the best price for them.

Or i could buy the blue callipers on somewhere like eBay, but not to sure about that....

Your grey unpainted calipers are upgraded Brembo's that came on some M Performance packs. The only difference as pointed out in another post is yours are likely the caliper made for the 340mm disks which can be ran under 18 inch alloys.
The M performance brakes you are referring to for upgrading are the 370mm kit. No need for that IMO.

If you want to upgrade the rears to the M performance, you will need the calipers, disk shields (which will involve removal of bearings to fit + correct handbrake shoes as they are different for the bigger disks).

If you are going to remove your current brakes and replace with the 370mm kit, I will be very interested in your front brakes.

PM if you are upgrading and have the old grey ones going spare.