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Model specific boards => Golf mk5 => Topic started by: Neil M on 06 September 2008, 12:58

Title: Brake vent
Post by: Neil M on 06 September 2008, 12:58
After replacing a new set of Brembo discs (£400) after two track days due to overheating and cracking, I've run some extra cooling ducting through the front fog lamp vents.

A friend who runs a Seat Cupra in the Sportmaxx Cup, has poped out the fog lamps to install the ducting but I didnt want to loose them so cut in a section of pipe to connect the Forge 65mm V2 ducting.

Its a bit tight getting it through, had to relocate the Horns and get it over the Forge pipe work from the Intercooler but have managed to direct it onto the back of the brake discs, will find out how well it works at Silverstone next week.

Thanks to the lads at AMD.

(http://i372.photobucket.com/albums/oo163/neilmelvin/Brakevent.jpg)

(http://i372.photobucket.com/albums/oo163/neilmelvin/Brakevent1.jpg)

(http://i372.photobucket.com/albums/oo163/neilmelvin/Brakevent2.jpg)

(http://i372.photobucket.com/albums/oo163/neilmelvin/Brakevent3.jpg)

(http://i372.photobucket.com/albums/oo163/neilmelvin/Brembo.jpg)

 
Title: Re: Brake vent
Post by: RedRobin on 06 September 2008, 14:43
After replacing a new set of Brembo discs (£400) after two track days due to overheating and cracking, I've run some extra cooling ducting through the front fog lamp vents.

A friend who runs a Seat Cupra in the Sportmaxx Cup, has poped out the fog lamps to install the ducting but I didnt want to loose them so cut in a section of pipe to connect the Forge 65mm V2 ducting.

Its a bit tight getting it through, had to relocate the Horns and get it over the Forge pipe work from the Intercooler but have managed to direct it onto the back of the brake discs, will find out how well it works at Silverstone next week.

....Is it okay to vent 'cold' air to the back of the brake disc? - I'm probably wrong but I thought I read somewhere that it wasn't a good idea to create a differential in temperature in either side of the disc.

I expect it's fine just delivering more air to the general area and wouldn't be fine if your vent pipes extended all the way close to the disc backs.
Title: Re: Brake vent
Post by: Neil M on 06 September 2008, 15:07
The duct just extends through the inner plastic panel of the wheel arch and should just cool the general area. It gets quite hot around the front wheels under heavy braking, I managed to melt my front plastic dust caps at Mallory park!
Title: Re: Brake vent
Post by: k4ith on 06 September 2008, 15:12
looks like your cars packing rocket launchers or something lol!
melt the caps :grin:, does this not take us back to the warm climate grills and aero dynamics thread?
Title: Re: Brake vent
Post by: Neil M on 06 September 2008, 15:34
looks like your cars packing rocket launchers or something lol!
melt the caps :grin:, does this not take us back to the warm climate grills and aero dynamics thread?

Friends have put 75mm and 100mm Diameter ducts into the wheel arch with no aero dynamic side affects on the track.
Only really going to be used for track days, it's only a 2 minute job to put the original ones back on.
Title: Re: Brake vent
Post by: k4ith on 06 September 2008, 15:52
Like the Brembo set up, if i could have splashed some cash i would have liked them but the R32 will do for now.
Title: Re: Brake vent
Post by: Neil M on 06 September 2008, 16:21
After 10 minutes on the track I wish I would have gone for it and had the RS4 365mm Disks with the 8 piston callipers, but this way I can always blame the brakes when people disappear into the distance.

Title: Re: Brake vent
Post by: Teutonic_Tamer on 07 September 2008, 09:15
....Is it okay to vent 'cold' air to the back of the brake disc?

Huh, yes!  But the vent isn't going to the back of the disc itself.  It's just going into the inner side of the wheel arch area in general - in the same way that the OEM vents in the undertray does.  :tongue:

For the ultimate cooling of disc brakes, a very concentrated and direct airflow of the coolest possible air, aimed straight at the inner side of the disc, near the hub - is the most reliable method.  This is how all F1, LMP and GT race cars are set up!  :rolleyes:

I'm probably wrong but I thought I read somewhere that it wasn't a good idea to create a differential in temperature in either side of the disc.

What a load of tosh.  :rolleyes:

Why, then, do road cars have one side of the disc open, in clear view through the alloys, yet the rear side is covered by the splash shields.  Also, why is it that on road car discs (conventional ones, not ceramics or any aftermarket ones), the outer face is connected to the disc "bell", which bolts to the hub, and creates a very postive path for heat conduction, yet the inner face is not, and therefore has no path for heat conduction!  :smug:

I expect it's fine just delivering more air to the general area and wouldn't be fine if your vent pipes extended all the way close to the disc backs.

Yes and no.  More air in the general area is better than less, however the ultimate and most effective cooling solution is where the ducts virtually touch the inner face of the disc.
Title: Re: Brake vent
Post by: Teutonic_Tamer on 07 September 2008, 09:18
The duct just extends through the inner plastic panel of the wheel arch and should just cool the general area. It gets quite hot around the front wheels under heavy braking, I managed to melt my front plastic dust caps at Mallory park!

Neil, those Brembos look lush  :cool: - where did you get them from?  Any links?  :smiley:

And are you still using the rear splash shields, or have you ditched them?
Title: Re: Brake vent
Post by: Teutonic_Tamer on 07 September 2008, 09:26
melt the caps :grin:, does this not take us back to the warm climate grills and aero dynamics thread?

Not really.  Those hot climes grilles were soley to provide cooling to an additional engine coolant radiator, and didn't actually provide any cooling to the brakes at all.  The fact they were never acutally fitted to any hot climes cars basically proves they were either compeletely innefective, or less effective than the standard set-up of a single rad and closed grilles.  Even hot climes with towing equipment never got them!  :smug:

Furthermore, for Neil's instance, it is being used for a very specific purpose - track days.  I don't recall seeing anything in the Golf Mk5 sales brochures, nor in the VW stealers, regarding any track day or motorsport useage for any Golf!  :nerd:

Melting the bolt caps really does enforce my concern over painting the edges of the discs (and the bells too), as discussed in a previous (but now deleted) thread!  :rolleyes:
Title: Re: Brake vent
Post by: Teutonic_Tamer on 07 September 2008, 09:36
After 10 minutes on the track I wish I would have gone for it and had the RS4 365mm Disks with the 8 piston callipers,

Or how about these 380mm lush puppies - available from your local stealer as an official retro-fit upgrade - for a mere £7,790 - plus VAT!  :shocked:

(http://i158.photobucket.com/albums/t108/Teutonic_Tamer/my%20B7%20RS4%20saloon/33058bdb.jpg)

(http://i158.photobucket.com/albums/t108/Teutonic_Tamer/my%20B7%20RS4%20saloon/bd220cd0.jpg)

(http://i158.photobucket.com/albums/t108/Teutonic_Tamer/my%20B7%20RS4%20saloon/brakes/AudiB7RS4saloon-84.jpg)

(http://i158.photobucket.com/albums/t108/Teutonic_Tamer/my%20B7%20RS4%20saloon/brakes/AudiB7RS4saloon-71.jpg)

Sorry for the thread hijack!  :embarassed:

but this way I can always blame the brakes when people disappear into the distance.

LOL
Title: Re: Brake vent
Post by: chungster on 07 September 2008, 10:08
i'm rather shocked the Brembo GT discs has only lasted 2 track days! But mind you i've never liked drilled discs due to their protential of "cracking" from the holes.

Those Audi Ceramics are monstrous. But you need 19" wheels for those.

I'll settle for the 345mm set up I'm about to have fitted in next 2 months. Much cheaper and should be fine for the GTI.
Title: Re: Brake vent
Post by: Teutonic_Tamer on 07 September 2008, 10:56
i'm rather shocked the Brembo GT discs has only lasted 2 track days!

Sadly, one of the bigest causes of adverse disc failure is soley down to "user error", such as failing to cool them down properly, or keeping the foot on the brake after a heavy stop.  :rolleyes:

But mind you i've never liked drilled discs due to their protential of "cracking" from the holes.

So how come all the "serious" OEMs, such as Porsche, AMG Mercedes, quattro GmbH - and the "quality" aftermarket suppliers, such as Brembo routinely use drilled discs without any probs?  :smug:  The only drilled discs which are prone to failure from cracking radiating from the drilled holes are cheap crap, which don't have the proper chamfering, nor disc tempering.  Look in MaxPower for examples!  :rolleyes:

Those Audi Ceramics are monstrous. But you need 19" wheels for those.

But 19s would look nice on a GTI !!  :drool:

I'll settle for the 345mm set up I'm about to have fitted in next 2 months. Much cheaper and should be fine for the GTI.

What, OEM R32/S3/LCR spec ones?  I'll be going down that route shortly.  :smiley:
Title: Re: Brake vent
Post by: RedRobin on 07 September 2008, 11:13
I'm probably wrong but I thought I read somewhere that it wasn't a good idea to create a differential in temperature in either side of the disc.

What a load of tosh.  :rolleyes:

Why, then, do road cars have one side of the disc open, in clear view through the alloys, yet the rear side is covered by the splash shields.  Also, why is it that on road car discs (conventional ones, not ceramics or any aftermarket ones), the outer face is connected to the disc "bell", which bolts to the hub, and creates a very postive path for heat conduction, yet the inner face is not, and therefore has no path for heat conduction!  :smug:

....Steady on, mate - I did say I was probably wrong and it wasn't me spouting the load of tosh.

Thanks for the rest of your post though - It confirms a few things :afro:
Title: Re: Brake vent
Post by: chungster on 07 September 2008, 11:43
Yes TT, I was gonna mention Porsche and some serious top end manufacturers manage to make drilled discs for their cars with no problems re cracking. I think its down to how they drill and when they drill the disc in the process of making it or something. But yeah some cheaper aftermarket ones often crack as they are purely done for cosmetic look reasons (form over function if you will)

Re the 345mm set up:

I've gone for a set off the Leon Cupra, supplied from a Seat dealer, at a stonking price! So still have red calipers.
Was shipped on friday, and should be arriving at my mates tomorrow or tuesday. Then we're gonna do a brake swap (mine onto his car and the 345mm onto mine)

Much cheaper than Brembo/AP's/Alcons and we're saving the fitting cost too.

It should be sufficient for my needs (i do like doing track days too) and cope with the plans i have for the car.

Title: Re: Brake vent
Post by: luca on 07 September 2008, 12:43
How much did you pay for the lcr brakes chungster?
I bought an r32 front set with 5kmiles on them for £330. Just need to mess about now and get the calipers painted red.
Anyone know if there are any decent aftermarket brake pads that will fit the r32 brake calipers?
Title: Re: Brake vent
Post by: chungster on 07 September 2008, 14:59
How much did you pay for the lcr brakes chungster?
I bought an r32 front set with 5kmiles on them for £330. Just need to mess about now and get the calipers painted red.
Anyone know if there are any decent aftermarket brake pads that will fit the r32 brake calipers?

Got the whole lot brand new delivered for £550!

Title: Re: Brake vent
Post by: bacillus on 07 September 2008, 15:07
Is it me or should TT resize his pics?
Title: Re: Brake vent
Post by: k4ith on 07 September 2008, 15:31
How much did you pay for the lcr brakes chungster?
I bought an r32 front set with 5kmiles on them for £330. Just need to mess about now and get the calipers painted red.
Anyone know if there are any decent aftermarket brake pads that will fit the r32 brake calipers?

I would suggest seperating the calliper from the piston, remove the 4 * bolts pictured below
 (http://i39.photobucket.com/albums/e170/b44fy/IMG_0338.jpg)
then either clean & spray the calliper or take to powder coaters.heres some pics of mine done, I also coated the calliper clip with heat res silver spray.
(http://i39.photobucket.com/albums/e170/b44fy/DSC00213.jpg)
(http://i39.photobucket.com/albums/e170/b44fy/DSC00214.jpg)
Title: Re: Brake vent
Post by: Neil M on 07 September 2008, 16:06
Yes TT 100% my fault with the cracked discs, stayed out a few laps to long at Bedford on pads that had seen better days and didn't cool them down properly, an expensive morning.
I'm after Brembo drilled disc replacements for the rear but their seems to be a problem with the main importers going bust I think.


Title: Re: Brake vent
Post by: luca on 07 September 2008, 17:16
How much did you pay for the lcr brakes chungster?
I bought an r32 front set with 5kmiles on them for £330. Just need to mess about now and get the calipers painted red.
Anyone know if there are any decent aftermarket brake pads that will fit the r32 brake calipers?

Got the whole lot brand new delivered for £550!



Thats a cracking deal. Will need to get mine sprayed and fitted now :grin:
Title: Re: Brake vent
Post by: DanGB on 08 September 2008, 17:05
http://www.seatcupra.net/forums/showthread.php?p=2064022  :wink:
Title: Re: Brake vent
Post by: DanGB on 08 September 2008, 17:05
interesting idea.. but im not sure that air is actually going to reach the disc is it???

Looking to do something simalar on mine, although the leon already has open vents.
Title: Re: Brake vent
Post by: luca on 08 September 2008, 17:36
Might just sell the R brakes and buy these. Would only be saving £150 quid after sorting the calipers out and the cupra ones are brand new
Title: Re: Brake vent
Post by: Top Cat on 08 September 2008, 17:47
Nice link Dan that's an excellent price. Has anyone on here done this upgrade and is there a noticeable improvement,  :smiley:
Title: Re: Brake vent
Post by: k4ith on 08 September 2008, 21:58
what size are the rear gti/ed30 set ups?
Title: Re: Brake vent
Post by: Top Cat on 08 September 2008, 22:01
what size are the rear gti/ed30 set ups?

Could be wrong but are they 312mil  :undecided:
Title: Re: Brake vent
Post by: SteveP on 08 September 2008, 22:16
what size are the rear gti/ed30 set ups?

Could be wrong but are they 312mil  :undecided:

Rears are 286mm, standard fronts are 312mm  :nerd:

So by the looks of things the rears are the same on the cupra as the GTI/ED30  :undecided:

I am very temped by the front brake upgrade,  but will probably wait until I at least need to replace the front pads and then convince SWMBO that pads are very expensive  :lipsrsealed:
Title: Re: Brake vent
Post by: Top Cat on 08 September 2008, 22:29
what size are the rear gti/ed30 set ups?

Could be wrong but are they 312mil  :undecided:

Rears are 286mm, standard fronts are 312mm  :nerd:

So by the looks of things the rears are the same on the cupra as the GTI/ED30  :undecided:

I am very temped by the front brake upgrade,  but will probably wait until I at least need to replace the front pads and then convince SWMBO that pads are very expensive  :lipsrsealed:
[/quote
]

So what happened to no more mods for the ED30  :rolleyes: :rolleyes: :rolleyes:

Title: Re: Brake vent
Post by: k4ith on 08 September 2008, 22:29
thanks, I was gonna buy the rears to match the fronts i fitted but no need now.
Title: Re: Brake vent
Post by: SteveP on 09 September 2008, 05:58
what size are the rear gti/ed30 set ups?

Could be wrong but are they 312mil  :undecided:

Rears are 286mm, standard fronts are 312mm  :nerd:

So by the looks of things the rears are the same on the cupra as the GTI/ED30  :undecided:

I am very temped by the front brake upgrade,  but will probably wait until I at least need to replace the front pads and then convince SWMBO that pads are very expensive  :lipsrsealed:

So what happened to no more mods for the ED30  :rolleyes: :rolleyes: :rolleyes:



But it wouldn't be a mod it would purely be a maintenance item  :wink: :grin:
Title: Re: Brake vent
Post by: RedRobin on 09 September 2008, 07:25
[post deleted - Error]
Title: Re: Brake vent
Post by: RedRobin on 09 September 2008, 07:30
I am very temped by the front brake upgrade,  but will probably wait until I at least need to replace the front pads and then convince SWMBO that pads are very expensive  :lipsrsealed:

So what happened to no more mods for the ED30  :rolleyes: :rolleyes: :rolleyes:

But it wouldn't be a mod it would purely be a maintenance item  :wink: :grin:

....You might have hit upon what's needed to successfully convince all SWMBO's! - The new (Milltek) exhaust is stainless steel and is preventative maintenance....All 'upgrades' are maintenance items, darling. 

:wink: :wink: :wink: :wink: :wink:
Title: Re: Brake vent
Post by: Teutonic_Tamer on 09 September 2008, 11:57
Is it me or should TT resize his pics?

Oi - I'm an expert with spanners and hammers, not bloody pixels!  :rolleyes:  :grin:
Title: Re: Brake vent
Post by: Teutonic_Tamer on 09 September 2008, 12:03
I would suggest seperating the calliper from the piston, remove the 4 * bolts pictured below
 (http://i39.photobucket.com/albums/e170/b44fy/IMG_0338.jpg)

You don't really want to be separating the caliper halves.  Whilst not relevant on these particular calipers, on opposed piston calipers, they are assembled in a jig to ensure absolute alignment between halves, for the internal fluid passages.


Don't know why the entire caliper aint painted though.  I'm sure that the S3 and R32 calipers are fully painted - though if I'm wrong, just a small slice of humble pie, as I have dodgy guts at the mo!  :sick:
Title: Re: Brake vent
Post by: Teutonic_Tamer on 09 September 2008, 12:07
Looking to do something simalar on mine, although the leon already has open vents.

But those "vents" do NOT supply air to the brakes!  :rolleyes:  Just like the Golf5, the cooling ducts for the front brakes on the Leon are taken from underneath the front bumper.

Title: Re: Brake vent
Post by: Teutonic_Tamer on 09 September 2008, 12:11
what size are the rear gti/ed30 set ups?

Could be wrong but are they 312mil  :undecided:

Rears are 286mm, standard fronts are 312mm  :nerd:

So by the looks of things the rears are the same on the cupra as the GTI/ED30  :undecided:

Yup, the rear brakes are 286mm, and are identical fit on the GTI, Ed30, LCR and Octy2 vRS (yup, Å koda vRS models now have red calipers, rather than pea green).