Stoptech's

[RedUn]

Had a quick search around here but I've not really come to a conclusion yet...

Has anyone got any experience of the Stoptech 380mm front and 355mm rear setup?

I was initially going to go AP but the non-floating rear disc has put me off slightly?

Any other BBK comments?

Thanks
Rick

[BMWZ4MC]

[GuidoK]

AP cant provide a rear floating disc?
Hmm by the looks of it (drawing) 1 piece steel? , not even aluminium center hat?

I know D2 racing also do floating front and rear in lots of sizes for reasonable prices.
I think you can even spec them with or without dust seals (no dust seals for track use)

I think movit will do anything custom you ask (very nice brakes that), but I think you have to ask for a quotation.
But I dont think they have a single piece caliper (single piece with fixed/cast bridge) is the most rigid, like the large brembo GT calipers:

[RedUn]

I'm not sure if AP can't provide one but I've never seen one and I've done hours of reading as per normal

The Brembo GT's are lovely but they are serious money! I did consider Alcon's but my friend ran a set through winter and it almost ruined them?

Will have a look at D2 and Movit now...

[GuidoK]

Strange to ruin a set of alcon brakes? What ruined them?
They use a nice strong monoblock caliper. Looks like a quality kit.

[RedUn]

Movit quote requested...

I think it was the salt that knackered the seals on the Alcons and just general corrosion? They are the same price as the Stoptechs although slightly smaller discs if that makes much difference?

[BMWZ4MC]

Alcon don't make a BBK that fits the Z4M. The CSL kit doesn't clear the track rod ends. I've been down that road before (fortunately I received a full refund).

[RedUn]

That's good to know!

[tertius]

The AP setup uses the standard M rear disc size - why do you need a floating rear disc?

I have the APs on my car, and the rears are more than up to the job, in fact over it really, such that I run a less aggressive compound in the rear to compensate.

[GuidoK]

If you have an aluminium hat the disc gets lighter if the size is the same.
Less unsprung weight and less rotational weight (less inertia) is always a plus.
And a floating disc can cope with more heat in theory (both due to warping and heat transfer to the bearing). If that's needed or not depends on the driver/useage. And a fully floating disc may have a little bit less parasidic drag.

[tertius]

If you have an aluminium hat the disc gets lighter if the size is the same.
Less unsprung weight and less rotational weight (less inertia) is always a plus.
And a floating disc can cope with more heat in theory (both due to warping and heat transfer to the bearing). If that's needed or not depends on the driver/useage. And a fully floating disc may have a little bit less parasidic drag.

All true but these are all going to be pretty marginal gains for 99% of drivers - a British Cycling level of consideration ...

[GuidoK]

Sure, rear brakes are far less used than the front brakes. Compared to the front brakes they hardly get warm, especially when the brake system is pretty much front biassed. Maybe with a custom brake setup with adjustable bias it will be different, but than you're driving pretty much a hard core racecar.
Although the weight reduction from an aluminium hat and the slightly less drag always is a (small) advantage. Whether its worth the cost is very debatable but thats a rear bbk in general too. A rear bbk is already for that 1% imho.
I have a rear bbk because it was extremely cheap (I spent about £300 in parts or so) and I thought it was fun to design a matching rear BBK to my front bbk. But my car would drive just as good with the stock rear brakes I imagine.
I would not spend 2k or so on a rear bbk even if it looks awesome. Maybe if I had unlimited money, but then I wouldnt be driving a Z4

[Beedub]

super happy with my APs!!

[RedUn]

Received a quote for the Movit setup, 370mm front discs and 6 pots and 342mm rear discs with 4 pots...~6.6k for the lot

As for the floating rears on the AP's, I feel like the rear discs are a downgrade from the OEM ones and my OCD won't let me run different discs front and rear although I've been out in a car with them on and they are very good!

[GuidoK]

That movit would be expensive.... I expected that
But look at D2 brakes.
You can choose between full floating and fixed (floating is still considerably more expenive), but fixed still has an aluminium centerhat and pretty massive discs I think from what I remember.
Look at the set that ba3bas has for sale, although that is for the normal Z4 so that wont fit the z4m, but you get an idea.
I know a person who has exactly the same set (same size/colour/spec etc) and it looks very impressive, certainly for that money. (ba3bas has that front+rear kit for sale for 2k). Somehow the d2 brakes are also cheaper in the uk than in mainland europe I think.

Whats the price on stoptechs and what do you get for that price btw?