MK5 Golf GTI
All Things Mk5 => Modifications & Technical Area => Performance Modifications => Topic started by: wizzo on May 03, 2010, 10:27:09 am
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Guys im thinking of cayenne 6 pots on r32 disks, i know they will need some modification but it has been done before, and i can do it :) im just worried that i wont gain anything over my stock GTI's performance wise, because of added weight? maybe ruing brake bias? because im not changing the rear? any input guys..
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ruining*
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The cayenne 6 pot on R32 just wont work without a lot of hassle.
However I have 2 full kits in stock that are a direct fit: http://www.mk5golfgti.co.uk/forum/index.php/topic,13669.0.html
Look halfway down the page :happy2:
I have driven a Mk5 with this kit on and they do feel very very good, they are a bit of a monster kit but for the price you wont find a better solution.
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PDT is probably right. I've looked at the brake set-up's he's offering and they are very good value for money. Even an R32 set-up would cost you around £400+ and wouldn't be anywhere near as good. :happy2:
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Thanx for the reply's guys.. its been done on golfmkv.com, yes the r32 disks with cayenne 6 pots need some grinding, its possible.. the direct fit is the mercedes gl450 rotors with cayenne 6 pots.. :) there is about 4 guys i've talked to on golfmkv that have them.. i would just need SS lines and some hub rings.. but im worried it would just be way to heavy.. and one guy warned me about ruining brake bias? any opinions.. the cayenne 6 pot fronts on gl450 rotors with stock gti rear?
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I would strongly suggest you speak with dave b. He knows all there Is to know about pretty much every caliper.
I think he mentioned once that the cayenne calipers aren't up to much?
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The Cayenne calipers weigh an awful lot (i know I i've held some!) and the size of the cylinder pots are big too, which isn't good for brake feel. They are designed to go on a 2.5 ton 4x4 and not a 1.35 ton hot hatch. Okay they look good, but as a practical brake kit they would be at the bottom of my list!
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The Cayenne stuff has a total piston surface area of around 56cm through to about 60cm - being honest its not a great pedal, the ideal total piston area is around 49-50 sq cm. You'll find with 6 pots with this piston surface areas that the pistons are split normally 27/31/36 or thereabouts. Even the smallest Q7 caliper is 30/34/38 might not sound like a lot but when you start multiplying the radius by its self and then by 3.142 you get huge volume that the 23.8mm master cylinder on the mk5 just cant push.....
They look rather good though :P
With no seal drag with pressure applied the smallest piston will deploy first, so you can "tune" calipers to feel better, they normally mess around with the smallest piston size to make brakes feel sharp, the bigger pistons will start to apply pressure when the smallest piston has reached the limit of its travel which is normally about 1mm.
Porsche 996TT calipers have a big piston split at 36/44mm but work very well, 38/42mm splits are also good (Ferrari 360/R8 Rear) works. 36/40mm works well on a smaller disc.
Personally the only 6 pots I would fit to my car would be AP CP5555's or CP7041 or Carrera GT rears or GT3 RS fronts, unless you want to blow over 1500 quid on brakes.
Regarding the R500 disc it is what it is, you need some mass to absorb the heat generated - no heat/no braking, even two piece 340-360mm assemblies weigh much more than stock, if you need big brakes its normally because you have a powerful car so corner entry speeds will be higher so you've got a lot of energy to get rid off. Dont forget the potential energy that needs dissipating is proportional to your speed squared so that if you can get to your braking point at 80mph instead of 90mph then its not just another 10mph (12%) you need to get rid off its about 25% more energy.
You pays your money I guess
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So what do u conclude dave? i wouldn't be getting much more than stock performance wise with the cayenne 6 pots?
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I think what Dave is saying is that by replacing the tiny original single pot calipers with a much bigger 6pot caliper you may lose some of the brake pedal feel and increase the pedal travel slightly.
I have now driven 2 cars with this conversion including an R32 we did today and the pedal feel was good, not as sharp as the original brakes but not as dull as some standard vauxhalls I have driven! The stopping power is immense compared to the standard brakes.
In total it comes down to what you want, if you want an extremely well priced kit that also looks :jumping: then the cayenne 6pot kit is very very good as long as you are happy to lose some of the pedal feel. If you double your budget then you can achieve the same stopping power with another kit and retain a much sharper pedal. I have never mentioned pedal feel to the customers that I have fitted 2 kits for on mk5's and they havent reported a bad pedal feel, if anything they have been delighted with the conversion. After all, the ECS stage5 big brake kit uses this caliper and with the same piston sizes, look on the American forums, they go mad for them!
The unfortunate thing with brake kits is that you dont get a chance to try before you buy and they arent the type of product that you can easily buy and sell on if you dont like them. I suggest you work out your budget and needs and buy the kit that suits these factors best.
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I would seriously reccomend this kit in this link which i have and i HIGHLY rate it!
http://www.mk5golfgti.co.uk/forum/index.php/topic,13542.0.html
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That R8 kit looks very nice. just a matter of finding some R8 rear calipers now..... just out of interets, what did that kit cost you Geordie?
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All in front and rear i think it worked out at around £1700 ish
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You really wanna give our dave a call. I think he has stock of the r8 rears
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That R8 kit looks very nice. just a matter of finding some R8 rear calipers now..... just out of interets, what did that kit cost you Geordie?
How many pairs do you want Dave :grin:
Swap you for something interesting..... :happy2:
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Only 1 set of R8s left now, I know whose got their name on them :party:
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do the R8s fit onto 312s as well. potential alternative to the porsche 4 pots
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Nope far too chunky, the smaller the caliper to fit the smaller range of discs the smaller the pistons. So you have to be careful about piston travel to make sure you dont start having the pistons come out too far.
The 312 disc is 25mm wide so you wouldn't use an R8 caliper with a design width size of 32mm, but you could consider using a 30mm wide disc. The boxster calipers have pistons that are 3mm shorter per side than say a 996 C2 caliper which is designed for a 28mm wde disc.
So what dod you decide on Wizzo?
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Sorry for the late reply guys, havent been on the computer for a while! :) I finally have all parts for my cayenne 6 pot conversion :)
- Brake Disks
- Cayenne 6 pots
- Brake lines
- Bolts for the caliper
All in all i got it for a very very cheap price..
Im planning on fitting soon :) i was just wondering if someone could give me a little walk through of flushing out all my fluid correctly.. i dont want to mess this up, and the cayenne calipers have the bleeding notch on both sides, i've done the gti caliper were it was just work from the furthest away (back right) and get to the closest (front left).. thanx everyone!
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One more question:
Do you think ill have trouble clearing the cayenne 6 pison calipers with Team Dynamic Pro Race 1.2's?
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be good to see the results...i was lookin for a 4 pot to put onto the s3 discs .....team dynamics have a good offset so you should be fine but im no expert
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One more question:
Do you think ill have trouble clearing the cayenne 6 pison calipers with Team Dynamic Pro Race 1.2's?
You could fit a double decker bus behind the TD's they are great for big brake kits. :happy2:
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One more question:
Do you think ill have trouble clearing the cayenne 6 pison calipers with Team Dynamic Pro Race 1.2's?
You could fit a double decker bus behind the TD's they are great for big brake kits. :happy2:
surely this is all dependant on the offset of the alloy in the first place????
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One more question:
Do you think ill have trouble clearing the cayenne 6 pison calipers with Team Dynamic Pro Race 1.2's?
You could fit a double decker bus behind the TD's they are great for big brake kits. :happy2:
surely this is all dependant on the offset of the alloy in the first place????
Tiz true but there is only one or two fitments that anyone can consider for the Mk 5 with the TD's sizes usually its 45 ET 8J. :happy2:
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:happy2:
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Also the design of the spokes lends itself greatly to the fitting. My other wheels are 45 ET as well and i need a 3 mil spacer to fit my brakes behind but with the TD's, same offset and you can get a sausage in between them.
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thanx for replies guys :) could someone answer my question on bleeding in the brakes :) ull find it a little higher up their :happy2: