M2/M3/M4 (F8x) Caliper Upgrade for Z4 M

[RvsBmw]

Hi all,

The car need new rotors and brake pads, so thinking about an upgrade. Car wont be tracked or maybe someday... Only fast road use.

Anyone have thoughts or experience with the swap from OEM calipers/rotors to the M2/M3/M4 (f8x) calipers and rotors? Its done on the M3 e46, but i havent seen it on the Z4 M e86/85.

Curious if:
- the brake balans is wrong?;
- It will fit with an e46 adapter, but will fit on the z4? By my knowledge the use the same parts so it should .

Thanks for reply's with thoughts/experiences or advice !

Greetz

[Daemonblitz]

I wanted to do this swap a long time ago, I ended up purchasing an M Performance brake kit for the F body 3 series at the time as well.
The cost involved and the custom work needed to make it fit didn't make any sense, so I ended up selling that kit and going with a performance BBK intended for the car (Stoptech in my case).
It is possible to do. yes but the depth of the rotor hats is so different between our cars and the "newer" ones, I would have had to either modify the suspension/knuckle/control arms heavily or to run completely different wheels with very different and shallower offsets to be able to use the brakes. Definitely not worth it.

[Westersund]

I would go with a proven swap instead, which is brilliant as well. There's adapters made for Porsche Boxster S/996 Carrera for both front and rear already and you can find the calipers at a reasonable price.

Fronts: 996351425 / 996351426
Rears: 996352421 / 996352422

[wdb]

I have a 996 and the front brake rotors are nowhere near the size of the Z4MC. Is there a specific 996 brake fitting that serves as an upgrade? Maybe something from the GT3?

[RvsBmw]

Originally Posted by wdb

I have a 996 and the front brake rotors are nowhere near the size of the Z4MC. Is there a specific 996 brake fitting that serves as an upgrade? Maybe something from the GT3?

The 996 caliper fits the 345mm rotor (front)
Other option is, but only have seen 1 person doing it, to go with the 6 pot 996/997.1 GT3. That one does fit the 370mm rotor.

[RvsBmw]

Originally Posted by Westersund

I would go with a proven swap instead, which is brilliant as well. There's adapters made for Porsche Boxster S/996 Carrera for both front and rear already and you can find the calipers at a reasonable price.

Fronts: 996351425 / 996351426
Rears: 996352421 / 996352422

Did you run this setup Andre on the 345 rotors?

[RvsBmw]

Originally Posted by Daemonblitz

I wanted to do this swap a long time ago, I ended up purchasing an M Performance brake kit for the F body 3 series at the time as well.
The cost involved and the custom work needed to make it fit didn't make any sense, so I ended up selling that kit and going with a performance BBK intended for the car (Stoptech in my case).
It is possible to do. yes but the depth of the rotor hats is so different between our cars and the "newer" ones, I would have had to either modify the suspension/knuckle/control arms heavily or to run completely different wheels with very different and shallower offsets to be able to use the brakes. Definitely not worth it.

Thanks sir, for reply. Have seen it being used on recent builds. Track guys saying, then go the route with the Porsche 4 pots+cooling, or go all the way with a specific BBK.

Also you have to modify, cut, the rear caliper to fit with the adapter..

I will skip this one, then..

[Westersund]

Originally Posted by RvsBmw

Did you run this setup Andre on the 345 rotors?

My Z4 M have the stock brakes still and that won't change anytime soon. My E46 M3 run the 345 mm discs but with Renault Megane RS CUP calipers up front and the Porsche calipers in the rear. But my Z3 Coupe will be fit with the Porsche setup all around with the 345 mm discs up front.

There's more stores that provide adapters but I bought my rear adapters here:

https://epytec.de/en/brake-system/ad...ke-disc?c=2047

https://epytec.de/en/brake-system/ad...ke-disc?c=2047


Or if you wanna go for the Renault Megane RS CUP brakes instead (This kit is installed on my E46 M3 up front):

https://freakyparts.co.uk/products/b...-big-brake-kit

[maupineda]

You may be interested in this read

https://nam3forum.com/forums/forum/m...swap-on-e46-m3

And here you hace a set if you want

https://nam3forum.com/forums/forum/c...-big-brake-kit

So it is doable but I do think that it is overkill

In my mind the better compromise is 6-pot 135i with rear 996 calipers

[RvsBmw]

Originally Posted by Westersund

My Z4 M have the stock brakes still and that won't change anytime soon. My E46 M3 run the 345 mm discs but with Renault Megane RS CUP calipers up front and the Porsche calipers in the rear. But my Z3 Coupe will be fit with the Porsche setup all around with the 345 mm discs up front.

There's more stores that provide adapters but I bought my rear adapters here:

https://epytec.de/en/brake-system/adapters/2221/bmw-e46-m3-brake-caliper-adapter-porsche-996-e46-m3-csl-345x28-brake-disc?c=2047

https://epytec.de/en/brake-system/adapters/2617/bmw-e46-m3-brake-caliper-adapter-rear-porsche-caliper-e46-m3-328x20-brake-disc?c=2047


Or if you wanna go for the Renault Megane RS CUP brakes instead (This kit is installed on my E46 M3 up front):

https://freakyparts.co.uk/products/bmw-e46-m3-brembo-4-pot-big-brake-kit

Thanks for reply. I've seen the clio or megane rs trophy brakes on m3's. Are they different than the Porsche?

[Westersund]

Originally Posted by RvsBmw

Thanks for reply. I've seen the clio or megane rs trophy brakes on m3's. Are they different than the Porsche?

Yes there is a difference, they don't use the same pads AFAIK. I believe the Megane calipers are a bit larger. If I would have built the M3 myself I would have used Porsche calipers all around for simplicity (balance/buying pads). The Porsche calipers are a well known modification and retains a great braking balance in the car.

[RvsBmw]

Originally Posted by Westersund

Yes there is a difference, they don't use the same pads AFAIK. I believe the Megane calipers are a bit larger. If I would have built the M3 myself I would have used Porsche calipers all around for simplicity (balance/buying pads). The Porsche calipers are a well known modification and retains a great braking balance in the car.

Thanks Andre. What do you think of the 996/997.1 GT3, setup I mentioned? I think with the Porsche setup you said the bias is shifting i a little bit towards the rear (not a problem for a z4).

[Westersund]

Originally Posted by RvsBmw

Thanks Andre. What do you think of the 996/997.1 GT3, setup I mentioned? I think with the Porsche setup you said the bias is shifting i a little bit towards the rear (not a problem for a z4).

Unless you're making the car into a serious track weapon the bigger GT3 brakes are just heavier, the braking power with the 345 mm discs and a monoblock caliper will stop the car just as well (even the stock calipers are good enough for that). The change to monoblock is more for feel and a consistent behaviour. If you can lock your front wheels the brakes are better than the tires, if you're runing slicks the brakes might (but probably not) need an improvement over the 996 calipers and stock discs.

As far a brake bias goes, yes it will shift it a little more towards the rear (comparing piston sizes). This is a common upgrade so I know that is works well, but if it doesn't you can always install a reduction valve on the line going to the rear calipers.

[RvsBmw]

Originally Posted by Westersund

Unless you're making the car into a serious track weapon the bigger GT3 brakes are just heavier, the braking power with the 345 mm discs and a monoblock caliper will stop the car just as well (even the stock calipers are good enough for that). The change to monoblock is more for feel and a consistent behaviour. If you can lock your front wheels the brakes are better than the tires, if you're runing slicks the brakes might (but probably not) need an improvement over the 996 calipers and stock discs.

As far a brake bias goes, yes it will shift it a little more towards the rear (comparing piston sizes). This is a common upgrade so I know that is works well, but if it doesn't you can always install a reduction valve on the line going to the rear calipers.

It's just for road and perhaps some use on the Ring someday. So the normal 996 will work then. Also I like to use the original size rotors. Visually there not the best but good when going back to oem.

[Westersund]

Originally Posted by RvsBmw

It's just for road and perhaps some use on the Ring someday. So the normal 996 will work then. Also I like to use the original size rotors. Visually there not the best but good when going back to oem.

The calipers are fit to both 996 and Boxster S, use the parts numbers in my initial post so you don't buy the wrong calipers.

[Duncan.B]

Originally Posted by Westersund

Or if you wanna go for the Renault Megane RS CUP brakes instead (This kit is installed on my E46 M3 up front):

https://freakyparts.co.uk/products/b...-big-brake-kit

I have just ordered this kit for the Z4M with pbs pro track pads as both front calipers had started to seize.

How are they on the e46 and what pads are you running ?

[Westersund]

Originally Posted by Duncan.B

I have just ordered this kit for the Z4M with pbs pro track pads as both front calipers had started to seize.

How are they on the e46 and what pads are you running ?

Sorry I've missed this post. They are working just fine on the E46 M3 without any issues. I've been runing some kind of StopTech pads (not sure what model) that the last owner modified to fit. But now I've swapped in PBS pads actually. What was the problem with your calipers? Siezed pistons or pads being stuck against the caliper?

[saintex]

These fit nicely and are lighter than stock

[lelandr]

Originally Posted by saintex

These fit nicely and are lighter than stock

My Z4M came with those same brakes, just in F&F yellow. Two things that annoy the hell out of me for those calipers: 1, the monoblock caliper requires removal for pad changes, which is annoying for a track rat, and 2, I think that the area ratio isn't quite right resulting in a low pedal.

[lelandr]

Originally Posted by Westersund

My Z4 M have the stock brakes still and that won't change anytime soon. My E46 M3 run the 345 mm discs but with Renault Megane RS CUP calipers up front and the Porsche calipers in the rear. But my Z3 Coupe will be fit with the Porsche setup all around with the 345 mm discs up front.

There's more stores that provide adapters but I bought my rear adapters here:

https://epytec.de/en/brake-system/ad...ke-disc?c=2047

https://epytec.de/en/brake-system/ad...ke-disc?c=2047


Or if you wanna go for the Renault Megane RS CUP brakes instead (This kit is installed on my E46 M3 up front):

https://freakyparts.co.uk/products/b...-big-brake-kit

Hi Andre, After reading through all of this, your setup looks good. Do you know if the Megane or 996 caliper setup fits within 17" wheels?

Thanks!
Lee

[Westersund]

Originally Posted by lelandr

Hi Andre, After reading through all of this, your setup looks good. Do you know if the Megane or 996 caliper setup fits within 17" wheels?

Thanks!
Lee

I've heard of people using 17" with the 345 mm discs and Porsche Boxter S/996 calipers, but it's very dependant on the wheel design. Personally I wouldn't bother because of the drawbacks or too little clearance between the disc and the wheel (brake cooling and heating of the wheel). Same goes for the Megane RS calipers, but I believe they build outwards a little more than the Porsche calipers.

[lelandr]

Originally Posted by Westersund

I've heard of people using 17" with the 345 mm discs and Porsche Boxter S/996 calipers, but it's very dependant on the wheel design. Personally I wouldn't bother because of the drawbacks or too little clearance between the disc and the wheel (brake cooling and heating of the wheel). Same goes for the Megane RS calipers, but I believe they build outwards a little more than the Porsche calipers.

Thanks. I have an ulterior motive for using 17"s as a track wheel. As tires are a significant consumable, the reduction in cost of as much as $50 PER TIRE is significant.