Brake vent

[Neil M]

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.











 

[RedRobin]

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.

[Neil M]

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!

[k4ith]

looks like your cars packing rocket launchers or something lol!
melt the caps , does this not take us back to the warm climate grills and aero dynamics thread?

[Neil M]

looks like your cars packing rocket launchers or something lol!
melt the caps , 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.

[k4ith]

Like the Brembo set up, if i could have splashed some cash i would have liked them but the R32 will do for now.

[Neil M]

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.

[Teutonic_Tamer]

....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. 

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! 

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. 

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! 

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.

[Teutonic_Tamer]

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  - where did you get them from?  Any links? 

And are you still using the rear splash shields, or have you ditched them?

[Teutonic_Tamer]

melt the caps , 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! 

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! 

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!