The beasts are fitted.....some crap pics page 15

The previous 10 pages are exactly what often spoils this great forum.

Back on topic....

Brakes looks great JE and hope the fitment goes smoothly :thumbsup:
 
We're still waiting on more pics of the complete set JE!

I'm interested on how they made the rear discs fit the inner 160mm shoes and how the rear caliper bracket is made ;)
 
A320_phill said:
The previous 10 pages are exactly what often spoils this great forum.
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Completely disagree with that comment - the majority of the posts on the previous 10 pages are what make this forum worth reading. This happened mainly because Jonny has purchased the BBK purely for looks, had he been buying it for track use he would never have gone for same size rotors front & rear - cf. Beedub's setup. I dare say the majority of people have never seen a BBK setup with such large rear rotors (in comparison to the fronts), I know I haven't, so discussion ensued... and it turned into a decent, reasoned, discussion on brakes, how they work, and if, indeed, there is any need to be concerned about over-breaking the rear when fitting larger brakes...

No-one was getting arsey or angry and none of it was ever intended as a 'pop' at JE - if I'm honest, the fact that JE started the thread because his new brakes had arrived was probably lost after the first couple of pages but that sort of thing never matters with Jonny because he'll probably start another thread about his brakes tomorrow :wink:


If all the comments were of the 'Ooh pretty brakes', 'Awesome Jonny' or 'When are they being fitted?' nature, threads would be very short, very boring, and people would learn nothing... :poke:
 
PerryGunn said:
had he been buying it for track use he would never have gone for same size rotors front & rear - cf. Beedub's setup. I dare say the majority of people have never seen a BBK setup with such large rear rotors (in comparison to the fronts), I know I haven't, so discussion ensued...
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I'm running with a 5mm smaller rear disc. Do you think that 5mm makes the big difference? I dont..
A lot of bmw stock setups are only 5mm smaller on the rear. I even dare to say that the difference in front and rear disc is exceptional for a lot of the z4's compared to the rest of the bmw lineup. That's because the rear axle of the z4 is based on the prefacelift e46 328i. It has small handbrake shoes. BMW doesn't make rear discs larger than 294mm with the 160mm drum/hat. But for the front they are willing to go to as far as 325mm, where all the e46 models with 325 front have 320 in the rear instead of 294mm. Oh and all on the same master cilinder.

Obviously bias is a point of attention (like a lot of aspects when working on brakes), but if the bias is a little bit messed up (which I doubt, but say if), it is
1. very easily detectable (just some hard brake tests on a quiet piece of road)
2. very easily corrected (put some more or less agressive pads front or rear (where needed).

These are things everyone can do (or should know how to do) when working(modding) on brakes or undercarrage in general.

If you can't correct it with pads.... then you have a seriously messed up setup :lol:
 
PerryGunn said:
No-one was getting arsey or angry and none of it was ever intended as a 'pop' at JE - if I'm honest, the fact that JE started the thread because his new brakes had arrived was probably lost after the first couple of pages but that sort of thing never matters with Jonny because he'll probably start another thread about his brakes tomorrow :wink:
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How true :rofl:
 
PerryGunn said:
Completely disagree with that comment - the majority of the posts on the previous 10 pages are what make this forum worth reading.
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+1

ranski said:
agreed, this isn't some gardening forum.
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+2

Absolutely agree.
This ain't a pair of red fluffy dice JE is hanging from his rear mirror, but a set of very expensive brakes that need to work safely.
I'm sure JE values the debate and advice and expects a bit of ribbing along the way.
IMO people aren't being mean spirited, but just want to make sure JE is going the correct route with these.
I've certainly learnt a lot in the past 10 pages and as Perry suggests, that is what makes this forum so great. :thumbsup:
 
GuidoK said:
PerryGunn said:
had he been buying it for track use he would never have gone for same size rotors front & rear - cf. Beedub's setup. I dare say the majority of people have never seen a BBK setup with such large rear rotors (in comparison to the fronts), I know I haven't, so discussion ensued...
Click to expand...
I'm running with a 5mm smaller rear disc. Do you think that 5mm makes the big difference? I dont..
A lot of bmw stock setups are only 5mm smaller on the rear. I even dare to say that the difference in front and rear disc is exceptional for a lot of the z4's compared to the rest of the bmw lineup. That's because the rear axle of the z4 is based on the prefacelift e46 328i. It has small handbrake shoes. BMW doesn't make rear discs larger than 294mm with the 160mm drum/hat. But for the front they are willing to go to as far as 325mm, where all the e46 models with 325 front have 320 in the rear instead of 294mm. Oh and all on the same master cilinder.
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I know that you built your own custom BBK so you sized them as you saw fit but I've only ever seen aftermarket BBK setups like Beedub's (370mm/328mm), the Alcon E85/6 front/rear set (365/343) and the AP front/rear set for the Z4M which are 356mm/325mm (note these are both respected companies that actually sell a 'set' for the E85/6 that they think gives the right balance) - I only know about these as I looked at them a while back in a moment of idle curiosity and weakness - but, luckily, they won't fit behind the Alpina wheels.

EDIT: Added the Alcon set that I saw at Birds
 
I sized them according to one of the most used setups bmw themselves uses. 3 series, 5 series, x3 etc. I was searching for a suitable rear disc, larger than the stock rear (as the stock bias is rather poor), and then you quickly come into this range. It was also what I was aiming for. The calipers I used were clearly designed to work with this size too.
And ga41 already wrote that he has a stoptech kit on his z4 that has 355 front rear with 6piston front, 4 rear, so that is in line with JE's setup.

As for same sizes, lots of other rwd cars use that (jaguar s /xf etc).... did you know that there is even a seven series that has a larger disc in the rear?

It's not that same (or nearly same) size disks front and rear is some kind of brake related faux pas that you hinted on in your previous post. A lot of bmw's have stock already more or less the same size front and rear (rear mostly 1-5mm smaller), and the master brake cilinder that is used in the z4 is also used in a lot of those setups. So on that side it's also not a strange thing.
 
GuidoK said:
It's not that same (or nearly same) size disks front and rear is some kind of brake related faux pas that you hinted on in your previous post. A lot of bmw's have stock already more or less the same size front and rear (rear mostly 1-5mm smaller), and the master brake cilinder that is used in the z4 is also used in a lot of those setups. So on that side it's also not a strange thing.
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Fair enough Guido, always happy to learn :thumbsup:
 
PerryGunn said:
A320_phill said:
The previous 10 pages are exactly what often spoils this great forum.
Click to expand...
Completely disagree with that comment - the majority of the posts on the previous 10 pages are what make this forum worth reading. This happened mainly because Jonny has purchased the BBK purely for looks, had he been buying it for track use he would never have gone for same size rotors front & rear - cf. Beedub's setup. I dare say the majority of people have never seen a BBK setup with such large rear rotors (in comparison to the fronts), I know I haven't, so discussion ensued... and it turned into a decent, reasoned, discussion on brakes, how they work, and if, indeed, there is any need to be concerned about over-breaking the rear when fitting larger brakes...
Click to expand...

Stoptech develop their kits on the actual car model in question before offering a kit for sale, at least they did with the Z4M which was developed on this guy's Z4MC http://www.mymcoupe.com/BrakeAndWheelMods.htm and they offer it with either 355-355 or 380-355 (the latter being much more expensive) so while i'm definitely not an expert I would think many factors determine the brake bias and not just rotor size.

In any case i'm very happy with mine either for street or spirited road or even track time.
 
ga41 said:
PerryGunn said:
A320_phill said:
The previous 10 pages are exactly what often spoils this great forum.
Click to expand...
Completely disagree with that comment - the majority of the posts on the previous 10 pages are what make this forum worth reading. This happened mainly because Jonny has purchased the BBK purely for looks, had he been buying it for track use he would never have gone for same size rotors front & rear - cf. Beedub's setup. I dare say the majority of people have never seen a BBK setup with such large rear rotors (in comparison to the fronts), I know I haven't, so discussion ensued... and it turned into a decent, reasoned, discussion on brakes, how they work, and if, indeed, there is any need to be concerned about over-breaking the rear when fitting larger brakes...
Click to expand...

Stoptech develop their kits on the actual car model in question before offering a kit for sale, at least they did with the Z4M which was developed on this guy's Z4MC http://www.mymcoupe.com/BrakeAndWheelMods.htm and they offer it with either 355-355 or 380-355 (the latter being much more expensive) so while i'm definitely not an expert I would think many factors determine the brake bias and not just rotor size.

In any case i'm very happy with mine either for street or spirited road or even track time.
Click to expand...


An expert or not, but you're one hell of an expert driver, as your videos prove. :thumbsup:
 
GuidoK said:
sars said:
Nictrix, I am neither defending or criticising his decision, I will say that I think upgrading his brakes before increasing the power is a good thing, but have insufficient knowledge to say whether whats purchased is suitable.
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So you're pretty much playing captain obvious.

I see a lot of speculation on bias, some people even seem sure that JE will have a bias problem......, but I hardly see anybody who actually have a bbk (front&rear) on their z4. Hardly anybody with hands on experience with the z4..... (just saying... :roll: )

ga41 has bbk all around on his z4m. Maybe beedub has? You all experienced huge bias problems after fitting? I havent.
And even if so.... its the first thing you test (you seek a piece of quiet road....), you feel with the abs where it locks up first. If the rear locks up first, that can mostly be very easily corrected with a less agressive pad at the rear or a more agressive pad at the front. It usually is that simple (and often says so in the manual....). I'm sure that the shop who'll fit the brakes will take it for a test drive and test the brakes. Not only for the bias, but also to see if everything else is ok (correctly bled the system etc)

Also I only see these discussions when people fitting brakes. Nobody starts these discussions when fitting different tyres/wider tyres... or coilovers/lowering their car....
That also has influence on grip and thus bias.... ;) (someone already said that it's the tyres in the end that stop the car)

aquazi said:
JE car will drive so slow with the unsprung weight on his 2.0 wont go anywhere near fast enough where brake balance matters.
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It will matter if he has to make an emergency stop, although the ABS will correct a lot (and you can't switch that off)
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Front and rear AP bbk for around 5 years now and have used them on track so many times I've lost count.. They are one of my fave mods to the car. Never had a single issue with them other than the noise the pads make and how expensive pieces are for them. Brake bias has never ever been an issue and i use aggressive endurance pads front and rear.
 
GuidoK said:
We're still waiting on more pics of the complete set JE!

I'm interested on how they made the rear discs fit the inner 160mm shoes and how the rear caliper bracket is made ;)
Click to expand...



THIS.
 
ga41 said:
Stoptech develop their kits on the actual car model in question before offering a kit for sale, at least they did with the Z4M which was developed on this guy's Z4MC http://www.mymcoupe.com/BrakeAndWheelMods.htm and they offer it with either 355-355 or 380-355 (the latter being much more expensive) so while i'm definitely not an expert I would think many factors determine the brake bias and not just rotor size.

In any case i'm very happy with mine either for street or spirited road or even track time.
Click to expand...
I notice that in your link the owner says 'My M Coupe was the test mule for StopTech's Z4 M 4 wheel BBK. It is comprised of components from their E46 line, but with some altering of brake torque to balance the system for the Z4 M' so even if the rotors are the same size Stoptech have made other adjustments in order to give the correct front/rear bias. I'm assuming that, in the examples Guido quoted (even the car with the larger rear rotors) similar adjustments have been made and I've fallen back into the old assumption of 'bigger rotors' = 'more brake torque' when I know (intellectually) that that's not necessarily the case - I shall chastise myself repeatedly (unless I can persuade my wife to do it :wink: )


I still feel that there's a fair amount of difference between

1. Braking systems that are sold/supplied as 'whole car' 4 wheel kits - your Stoptech system, the AP systems and even the OEM setups that Guido describes, as all of those have been tested by the manufacturer/supplier on that model of car and they certify that they will work safely on that car.

2. Brake kits that are sold seperately for each axle and a customer is free to purchase/install any combination they wish - all the manufacture/supplier certifies is that each kit, in isolation, will work on the car they are supplied for. Any mismatch will be the buyer's responsibilty so they should ensure that either they know what they are doing or should take expert advice beforehand


This means that

1. Is more expensive as the manufacturer has done all the research and testing in order to produce a certified kit (or kits) for a specific car.

2. Is cheaper as the manufacturer is producing kits that they adapt to fit multiple vehicles, but it places the onus on the customer to do more research to ensure that the combination of kits they select is suitable for their vehicle.
 
Poor old Jonnie, all he wanted to do was post up some cool rotors he'd purchased. Crack on and fit them and post up pics when finished. As for bias, if valve required it's fairly simple to have fitted and you'll have a hoot setting it up. Obviously on a a airfield tho.
Seriously glad I didn't post up my brake upgrade on my V10 project, I would've needed a degree in physics to pan it off. Only hint is there's 24 Pistons.
 
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