E46 Brake upgrade

[2skiddy]

Anyone got any CSL front discs and caliper brackets? I am going to try this first to upgrade my E46 M3, with wind to them and upgraded fluid and pads.
Cheers.

[Franzino]

Paul_M3 said:

AP only do a 6 pot kit for the e46 M3. The 4 pot kit is for the rear.

Most e46 M3 brake kits are 6 pot on the front.

I have the AP kit on the front of mine, and it's fantastic. It is also designed to fit under OEM 18" wheels as well as the 19" ones.

You only have the front AP 6-pot on your M3 and the oem M3 brakes at the rear? How is the brake balance and what pads are you using?

[Franzino]

youdsy said:

ok thanks for that, 6 pots it is then. I knew that AP did the 4 pots for the rear, just assumed that they did a 4 pot caliper for the fronts.

I have the 19"CSL alloys so clearance shouldnt be an issue. Looking at the kits, there are a few to choose from in terms of size and style of disk. Any recommendations as to which one i should go for?

thanks

I wanted a BBK kit from Stoptech... The front BBK could fit with the factory 18" and 19" e46 M3 wheels. I did a measure and the 6-pot Stoptech did not fit with my oem 19" CSL wheels. There is not enough clearance! The problem wit the CSL wheels is that the spokes of the wheel don't go down in a straight line. They are crooked and that's why there was not enough clearance for the caliper. Th side of the caliper touched the wheel. So it's possible the AP kit will also not fit on CSL wheels without the use of spacers... Unless the AP 6-pot kit is smaller in size then the Stoptech 6-pot kit, that would be good news! I'm still searching for a BBK that fits with my 19" CSL wheel and I don't want to use spacers..

[Franzino]

Paul_M3 said:

They do two calipers, one is slightly thinner and designed to fit under 18" OEM wheels as well.

I would suggest getting this one. The performance difference will be minor, and it might be useful at some point.
(I also had CSL wheels when I bought the kit, but a few months later bought some OEM 18" wheels to use on track only. I wouldn't have been able to do this with the thicker caliper)

Did the front AP brake kit fit without spacers on your car with the CSL wheels?

[shim]

Franzino said:

youdsy said:

ok thanks for that, 6 pots it is then. I knew that AP did the 4 pots for the rear, just assumed that they did a 4 pot caliper for the fronts.

I have the 19"CSL alloys so clearance shouldnt be an issue. Looking at the kits, there are a few to choose from in terms of size and style of disk. Any recommendations as to which one i should go for?

thanks

I wanted a BBK kit from Stoptech... The front BBK could fit with the factory 18" and 19" e46 M3 wheels. I did a measure and the 6-pot Stoptech did not fit with my oem 19" CSL wheels. There is not enough clearance! The problem wit the CSL wheels is that the spokes of the wheel don't go down in a straight line. They are crooked and that's why there was not enough clearance for the caliper. Th side of the caliper touched the wheel. So it's possible the AP kit will also not fit on CSL wheels without the use of spacers... Unless the AP 6-pot kit is smaller in size then the Stoptech 6-pot kit, that would be good news! I'm still searching for a BBK that fits with my 19" CSL wheel and I don't want to use spacers..

AP kit front and rear fits under BMW 19 inch CSL rims, BMw 18 and 19 inch E46M3 rims without spacers. Although the original E46 AP kit CP5555 did not fit under 18 inch rims this was changed and the CP5575 kit for the last 4 years.

You may have issues on other replica rims that run different offsets as this only applies definitely to BMW rims.

[Franzino]

I know the AP brake kit for the e46 M3 CSL and the normal e46 M3 (with 19" CSL wheels) can fit without spacers.

I still did not have a definitive answer if the 19 CSL wheels can fit without spacers with the front AP brake kit CP5575-1010 (Z4M kit with the smaller caliper). I have received a template for the AP Z4M kit that can be used to verify fitment.

The result; If I look at the template there is space of only 2mm between the front brake caliper and the CSL wheels. I can just fit the metal lid from a can of soda between the caliper and the wheels. That's not a lot of space.

Any thoughts?

Edited by Franzino on Sunday 13th March 18:29

[foz01]

I am doing the 996 Porsche brembo caliper conversion, font and rear with brackets using csl front discs. All up significantly cheaper than the front AP kit

[Franzino]

Cheaper... But better?

[mat205125]

Franzino said:

Cheaper... But better?

Exactly!

Obviously swapping to Porsche brakes addresses the M3's fundamental problem of being specced with floppy single piston lumps of iron or sliders for calipers, however another benifit of the AP setup are huge, thick, high spec rotors that are more than up for the job of dealing with the forces involved with hauling the M3's mass up from high speeds repeatedly.

Do the CSL discs really offer that much improvement over the standard M3 discs? Do they still restrict on-track durability and performance.

[Franzino]

mat205125 said:

Do the CSL discs really offer that much improvement over the standard M3 discs? Do they still restrict on-track durability and performance.

I a have Z4M, so I already have the brake set-up from the BMW M3 CSL. The BMW M3 CSL brakes are the same as the one on the Z4M and they both don't preform very good on a track.

A lot of people fit a BBK (and also the Porsche brakes) mainly for the looks. I don't care about the look of a BBK kit. Ok they look good, but that will never be the reason why I would buy them. For me it's the upgraded brake power (and less fading) that's the most important. Brakes are an important element on a car driven on a track and for me it's not something were I want to be cheap. If I fit a BBK, then I'm doing it good and I will buy something from a well known brand and not something put together with parts from different brands. But that just me...

Edited by Franzino on Monday 14th March 12:56

[Cheburator mk2]

Lol,

seriously,

I must be in the company of track masters here... The only problem with the BMW CSL OEM Braking System is the single pot calipers and small pad size... The discs are as good as it gets for the size/price. I have the 996 front and rear calipers on my Z4MC and I can still lock the front wheels before the ABS kicks in... The AP Racing one is a good kit too, but the fronts alone cost double the price of a brembo conversion for the whole car and they are definitely not twice as good as the Brembos...

Moreover, there was a number of lower budget E46M3s racing in the 24hrs of Nurburgring last year with the 996 kit. Surely, it if is good enough for them it must be good enough for most of us?

[Franzino]

Cheburator mk2 said:

Lol,

seriously,

I must be in the company of track masters here... The only problem with the BMW CSL OEM Braking System is the single pot calipers and small pad size... The discs are as good as it gets for the size/price.

That's true. The discs are not the problem! I never said the oem CSL discs are a problem. I'm not a track master; I only do 10-12 trackdays a year and some trips to the Nurburgring (I live 2 hours from the NS). A real track master would buy a GT3, CSL and not a Z4M roadster like me

Cheburator mk2 said:

I have the 996 front and rear calipers on my Z4MC and I can still lock the front wheels before the ABS kicks in... The AP Racing one is a good kit too, but the fronts alone cost double the price of a brembo conversion for the whole car and they are definitely not twice as good as the Brembos...

I know there are some cheaper solution for the Z4M when you take something from another car. I can also fit a set of modified BMW Performace calipers on my car.

When you are talking about the Porsche 996 front and rear calipers; I presume you mean using the set-up that was originally designed for the Porsche 996? That's how I understand it.

I don't feel comfortable with putting something on my car that's not initially designed for my car. Brembo engineers each kit for a specific model application, with unique piston size variation for optimum brake balance, increased brake torque and thermal capacity. Brembo makes great brakes! But I would rather have a specific kit designed for the Z4M, then something designed for another car.

Maybe AP racing is really expensive in the UK?
Here are some BBK prices (6 pot front & 4 pot rear) in my country;
A full Brembo Z4M GT kit cost £3.500 (excl. tax). A full AP racing Z4M kit costs £2.930 (excl. tax). A full Stoptech Z4M kit costs £3.650 (excl. tax). The only 6-pot brakes I can fit without spacers in front is the AP kit (that was a big concern for me) and it's also the cheapest from these three...

[ATM]

Cheburator mk2 said:

Lol,

seriously,

I must be in the company of track masters here... The only problem with the BMW CSL OEM Braking System is the single pot calipers and small pad size... The discs are as good as it gets for the size/price. I have the 996 front and rear calipers on my Z4MC and I can still lock the front wheels before the ABS kicks in... The AP Racing one is a good kit too, but the fronts alone cost double the price of a brembo conversion for the whole car and they are definitely not twice as good as the Brembos...

Moreover, there was a number of lower budget E46M3s racing in the 24hrs of Nurburgring last year with the 996 kit. Surely, it if is good enough for them it must be good enough for most of us?

I have the 6 pot AP calipers on the front of my e46. I bought it as is. It has some small 2 pots on the back. The front discs are massive with alu bells. I think they're performance friction from what I remember when I bought the car. The rear discs are standard m3 - my car is not an m3. My rear discs are looking badly worn so these need to be changed. I'm thinking about buying the AP 4 pot rear kit to match the front. AP can supply this to use the standard m3 disc or supply solid single piece discs of the same size.

The brakes squeel quite loudly now but I can't figure out if this is from the front or the rear. I'd prefer squeel free if possible.

My main problem now is that I can lock a front wheel quite easily. Once I do the ABS does nothing. I'd like a working ABS system. I'm wondering if something is not right with my car because the ABS isn't working. My orange ABS light illuminates when I fire up the car and then goes off. So I am presuming that it is not alerting me to any faults.

When the previous owner fitted the v8 engine he relocated the ABS module with all the pipes going in and out. He also changed all hoses to flexi throughout the car. One of my friends thinks this could be causing the problem and I should have these replaced with rigid hoses where possible.

I'm wondering if the front two wheels are piped up the wrong way round because when it locks a wheel the car seems to stop braking altogether. The only reason I can think of for this is that when the ABS detects a locked wheel it should release pressure to that wheel. If it is releasing pressure to the other front wheel then this would make the locked wheel remain locked and the free wheel would spin freely and not brake at all.

Here is a pic of my rear setup.

[Chessers]

I did the CSL upgrade on mine, plus braided lines, ATE super Blue and better pads. It made a huge difference in brake fade. Didn't track mine so was suitable for fast road.

[ATM]

Chessers said:

I did the CSL upgrade on mine, plus braided lines, ATE super Blue and better pads. It made a huge difference in brake fade. Didn't track mine so was suitable for fast road.

Does the CSL just have bigger front discs?

[motors]

Front discs are bigger, but if your going to track car ap's with pagid pads is the way to go

[Beedub]

my APs are awesome, i think the 6pot / 4 pots are overkill on the z4m as per simpsons advice, they also warned the rear 4pot can cause rear lockups ( i haven't experienced this however) incredible breaking, the only thing i don't like is how close they sit to the barrel of the 18" rim, hardly ANY space..... i swap between the APF404 and a dedicated track pad.

[ATM]

Beedub said:

my APs are awesome, i think the 6pot / 4 pots are overkill on the z4m as per simpsons advice, they also warned the rear 4pot can cause rear lockups ( i haven't experienced this however) incredible breaking, the only thing i don't like is how close they sit to the barrel of the 18" rim, hardly ANY space..... i swap between the APF404 and a dedicated track pad.

Yes I have problems with clearance for the balance weights on my fronts. They have to be placed out of the way of the caliper because there isn't enough clearance for them.

Ok so it sounds like I'm best to stick with the calipers I have on the back and get some new standard m3 discs?

[Beedub]

ATM said:

Yes I have problems with clearance for the balance weights on my fronts. They have to be placed out of the way of the caliper because there isn't enough clearance for them.

Ok so it sounds like I'm best to stick with the calipers I have on the back and get some new standard m3 discs?

same here.... my caliper basically sits inside the wheel drum, if a stone was to become lodged ( small chance i guess) it would cause some damage,

[ATM]

Beedub said:

ATM said:

Yes I have problems with clearance for the balance weights on my fronts. They have to be placed out of the way of the caliper because there isn't enough clearance for them.

Ok so it sounds like I'm best to stick with the calipers I have on the back and get some new standard m3 discs?

same here.... my caliper basically sits inside the wheel drum, if a stone was to become lodged ( small chance i guess) it would cause some damage,

Fitted some O Z wheels to my beast. Tiny bit more clearance from these wheels. I get occasional lock ups. Not sure if it is the front or the back. Does switching to big brakes mean lockups are to be expected or is something wrong with the car?