Then, surely, it's the tree stopping you and not the brakes...Bing said:They can if they make you spin out and hit a tree![]()

PerryGunn said:Then, surely, it's the tree stopping you and not the brakes...Bing said:They can if they make you spin out and hit a tree![]()
![]()
PerryGunn said:IAWTP, if you look at the suppliers it appears that, as long as they have a bracket fitment for your car, they will let you select any combination of front and rear sizes you want. There may be some but I haven't seen any sites that sell D2, K Sport etc. as a matched 4 wheel kit only as independent front and rear sets. If you want 380mm rears and 220mm fronts, they'll sell them to you. It's 'buyer beware' and if you choose to fit (or have fitted) mismatched front & rear sets to your car, it's your responsibility to ensure that your car will be safe.Ed Doe said:What a ridiculous thing to say! Jonny has gone to a professional outfit yes - a brake supplier. Someone who wants to sell brakes. "Yes sir, they fit your car". I would imagine the brake components will be warrantied against any mechanical defects, but I highly doubt there would be come-back once they are fitted - particularly if it is a set-up issue. "Oh your car is braking too much at the rear? The brakes are working then - fit a bias valve" will be the response - I'd put money on it. Furthermore there is absolutely no legal or documented evidence to prove categorically that D2 "explicitly confirm that these calipers will work in perfect harmony on Jonny Essex's 2.0 E85 Z4 with the red roof etc.etc.etc.)."sars said:I love reading this stuff and comments made by would be engineers, I get them all day at work and whilst it sometimes gets frustrating with some really interesting questions (and for the record there are no such thing as a stupid question) I try and answer/educate when ever I can.
But seriously guys, Jonny has gone to a professional outfit, told them what he has and they have given him what they believe, in their professional opinion, what he needs. It's not like he's (jonny) gone down to the pub and picked up some dodgy brake parts from bodget and scarper and you're wondering if the master cylinder is big enough![]()
So get real, we are talking brakes, do you honestly believe a professional outfit, an American manufacturer with TUV ISO 9001 certification, would supply an aftermarket kit that could possibly kill someone without making sure it is fit for purpose.
They have told Jonny that the calipers fit and work. They will. It will naturally fall to Jonny himself, or to the unfortunate company lumbered with fitting them and setting them up for Jonny to fit a bias valve to get the brake bias to a usable balance front/rear - let alone back to OEM balance.
It is extremely likely the company will be used to dealing mostly with people who are tracking their cars and have reached the limits of their OEM brake set-up. These people will be resonably clued up on brake balance, and cruicially prepared to do their homework, and fiddle to get the best out of the set-up. Not just bung them on and hope for the best....
I'm afraid I don't care what anyone has told Jonny to date, I'll state now for the record; those brakes once fitted are going to cause the rear of the car to be massively over-braked - in my opinion to a quite alarming, and potentially dangerous degree - without a bias valve and someone who knows what they're doing to set it up.

Yes people have fitted BBKs, I don't think people are having a go at Jonny just trying to make him understand that putting the same size rotors front and rear may not be the most sensible thingBing said:Yeah, but they started it, and that's enough reason for blame where I come from![]()
In all seriousness, everyone's having a pop at Jonny because... It's Jonny. Loads of people on here have fitted big brake kits and I bet none of them have provoked a thread 8 pages long in so little time. Hopefully Jonny will be getting professionals to fit them who understand the engineering and work with him to get it right. So how about we all just appreciate the beauty of those pieces of mechanical art, and let him get on with it...
PerryGunn said:Yes people have fitted BBKs, I don't think people are having a go at Jonny just trying to make him understand that putting the same size rotors front and rear may not be the most sensible thing
And, from what he's said, he's not getting professionals to fit them...
Bing said:PerryGunn said:Yes people have fitted BBKs, I don't think people are having a go at Jonny just trying to make him understand that putting the same size rotors front and rear may not be the most sensible thing
And, from what he's said, he's not getting professionals to fit them...
Okay, I take that back, just read he's doing it himself. Feck me, I wouldn't, even if I knew how. This is serious engineering after all, not just new pads and hoses...
Though I do think hat for some reason people just like having a pop at Jonny...
As a matter of interest, what rotor sizes do you run front/rear?Beedub said:i love the brakes and i LOVe the fact your fitting them yourself... i did mine too and it was incredibly satisfying.
sars said:Ed Doe, first of all thanks for the research, what you have copied is spot on, however it is a generalisation and the actual problem is more complex than written, it's dumbed down for the internet. The problem with generalisation is that by its very nature it is unspecific, brake bias is fundamentally calculated from the centre of mass of the vehicle, as we all know this changes with acceleration, so for road use designers will stick to a pretty large margin of safety given the infinite variability of the road and car, for racing cars it becomes track specific (in F1 they even change brake bias through the lap).
I have no idea of the % bias of Jonny's zed, I would bargain no one here does, but I guarentee the manufacturers of these brake products will have done their math and will recommend something suitable, at the end of the day Jonny asked and they told, they ARE culpable
sars said:Oh I should have added, front brake bias is probably worse than rear brake bias, If your front wheels lock you can't steer
PerryGunn said:As a matter of interest, what rotor sizes do you run front/rear?Beedub said:i love the brakes and i LOVe the fact your fitting them yourself... i did mine too and it was incredibly satisfying.
CornishRob said:Are the rotors fixed or floaters?
How do the aftermarket kits decide if they use fixed or floaters?