Using a BBK from a 'normal' M3

Porter · 24-10-2011, 08:01 PM

Hi guys - I'm after some brake know-how, please.

I used to have a normal E46 M3. The best thing I did to that car was to put a StopTech BBK on the front. It's a 4-piston caliper and 355mm disc set up.

I've been emailing StopTech in the 'states, who have said that I should fit a different StopTech kit to retain the correct front/rear balance. They say that, as the rear caliper pistons on the CSL are larger (46 vs 42mm?), I need calipers with larger pistons on the front. This all makes eminent sense so far.

My quandry comes when I look at other manufacturers' kits (including AP, as far as I can make out). They seem to offer only one front BBK, for both the M3 and the CSL. So I am left wondering how much difference there is between the 2 StopTech kits and whether I really need to buy different front brakes.

I am happy with the other options (pads/fluid/brake less etc), but I tried all those on the M3 and I am sure that I will eventually go for a BBK on the CSL.

Thanks for taking the time to read all this rubbish. Grateful for any ideas - the wife will have a hissy seizure if I tell her I want new brakes.

s.mac · 24-10-2011, 08:28 PM

I transferred my M3 BBK to the CSL with no issues, the M3 is heavier so if it works on that, it will work on the CSL (this was my take on it)
I only changed later to the AP as I saw one for sale, I couldn't tell the difference. Although it is easier to get the AP replacement parts.

Porter · 24-10-2011, 08:29 PM

Quote:

Originally Posted by s.mac

I transferred my M3 BBK to the CSL with no issues, the M3 is heavier so if it works on that, it will work on the CSL (this was my take on it)
I only changed later to the AP as I saw one for sale, I couldn't tell the difference. Although it is easier to get the AP replacement parts.

That makes sense. Was that just a front kit you transferred, or all 4 corners?

s.mac · 24-10-2011, 09:44 PM

all 4 corners, all 4 pots

**glendog74** · 25-10-2011, 05:14 PM

Quote:

Originally Posted by s.mac

all 4 corners, all 4 pots

Was that your fake Brembo kit Steve?

**CraigMillwardCroft** · 25-10-2011, 05:22 PM

Can you not tell the wife you don't moan when she gets new hoover bags

24-10-2011, 08:01 PM	#1
Porter S4 - Getting the hang of it Join Date: May 2011 Posts: 135 Casino cash: $4767	Using a BBK from a 'normal' M3 Hi guys - I'm after some brake know-how, please. I used to have a normal E46 M3. The best thing I did to that car was to put a StopTech BBK on the front. It's a 4-piston caliper and 355mm disc set up. I've been emailing StopTech in the 'states, who have said that I should fit a different StopTech kit to retain the correct front/rear balance. They say that, as the rear caliper pistons on the CSL are larger (46 vs 42mm?), I need calipers with larger pistons on the front. This all makes eminent sense so far. My quandry comes when I look at other manufacturers' kits (including AP, as far as I can make out). They seem to offer only one front BBK, for both the M3 and the CSL. So I am left wondering how much difference there is between the 2 StopTech kits and whether I really need to buy different front brakes. I am happy with the other options (pads/fluid/brake less etc), but I tried all those on the M3 and I am sure that I will eventually go for a BBK on the CSL. Thanks for taking the time to read all this rubbish. Grateful for any ideas - the wife will have a hissy seizure if I tell her I want new brakes.

24-10-2011, 08:28 PM	#2
s.mac CSL Register Uber-poster! Join Date: Jun 2008 Posts: 4,247 Casino cash: $15600	I transferred my M3 BBK to the CSL with no issues, the M3 is heavier so if it works on that, it will work on the CSL (this was my take on it) I only changed later to the AP as I saw one for sale, I couldn't tell the difference. Although it is easier to get the AP replacement parts.

24-10-2011, 09:44 PM	#4
s.mac CSL Register Uber-poster! Join Date: Jun 2008 Posts: 4,247 Casino cash: $15600	all 4 corners, all 4 pots

25-10-2011, 05:22 PM	#6
CraigMillwardCroft CSL Register Uber-poster! Join Date: Oct 2010 Location: Marlow Posts: 3,973 Casino cash: $18153	Can you not tell the wife you don't moan when she gets new hoover bags