Venting In Under Arch Cover.

[JAMES]

back to the original post,am i right in saying that the heat causes the brake fluid to boil and releases air when boiled into the brake lines which causes the pedal to go spongy.i think that by changing brake fluid it has a higher withstanding of heat so lasts that extra mile.when the actual brake components overheat you just get less friction which means longer stopping distances or very little brake response

[Scatmans3]

A big [img]images/graemlins/thumb.gif[/img] to Andiroo, you're one of mine [img]images/graemlins/rocker.gif[/img]
Having said that, how exactly did you handle drivetrain issues having raised boost to that sweet sweet 2.25bar and yet using the emergency bottle? I take it that you don't use'em Modena-destroying-Quattro-launches very often. (I do it on a daily basis.)

Regarding handling improvement (I own a S3) I have found a Quaife front differential wich seems to be pretty neat, but would have me rethink all my cornering abilities. But on longevity of the drivetrain, I do know that Torsen or Haldex will let you abuse them anyway you like and won't let you down *easily*, but improvements are always welcome!
Any tips?

Cheers!
Alexander
[img]images/graemlins/kissmyrings.gif[/img]

(btw: don't ask about silverwing. most people hate it.)

[Andiroo]

JAMES you are correct [img]images/graemlins/thumbs.gif[/img] Any heat that cannot be dissapated will either boil the fluid (unless you use somehting like Catrol SRF4.1 [img]images/graemlins/wink.gif[/img]) or glaze the pad surface, which you can reduce by using a pad with more ceramic compund ie Pagid Sport Yellows for example.

The key, as the guys point out, is to try and dissipate the heat quickly either thru flowing air or other medium. Hot air just compounds the issue (and our intercoolers get rather hot on trackdays) and IMHO either a air ducting system with the feed not being from behind the intercoolers and/or water cooled calipers from AP Racing (still awaiting the hopeful verdict on this one).

There are a few ideas given to me which we will toy with & discuss over the coming 6 months which may give some much needed solutions to our common problems [img]images/graemlins/tongue.gif[/img]

Alexander, thanks for the nice words. The main problem on an RS4 with launches is the clutch and gearbox. I currently have a 550ft/lb rated paddle clutch with one of Tanoga's lightened flywheels. On the gearbox front we will either cryo freeze the input shaft, which is the weak link, and maybe change the ratios altogether. Ideally a sequential box and matched carbon paddle clutch would be my way to go, which would suit trackdays and qtr miles. Reckon the OEM drivetrain is OK for the power, but who knows, as it's never been tried really. Maybe carbon fibre shafts would help, although they will be much lighter and will therefore put more load on the drivetrain. Let's see how we get on [img]images/graemlins/wink.gif[/img]

Andiroo



Andiroo

[JAMES]

wouldn't a different set of rims help as apparently all porsche wheels are designed to cool the brakes as well as look good.
maybe even just for track days.

[Riz_RS4]

what about having hoses from the front of the car to the brake area? ducting or ram-air type of thing? high pressure air hoses with the pump under the bonnet?

[sitas3]

I'd have thought one of the biggest obstacles to sufficient brake cooling in the front is that the wheel basically deflects air away that is being passed through the front bumper etc (and the brake caliper/disc assembly is hidden inside the wheel.)

Or have I had a tinnie too many tonight!! [img]images/graemlins/jump3.gif[/img]

[Andiroo]

The Sportec rims are questionable as to how well they ventilate, especially as mine are 10" wide - do they ventilate internally better or worse than an 8.5"? Don't know really.

Good point re the inner wheelarch Simon. When you think about it it is so full of tyre and rim, would any cool air get to the calipers and discs? Probably not IMHO. Bushy's comment re the ducting and vents fixed to the caliper (ala VW Phaeton) are probably the most logical and effective, save for water cooled calipers.

And as for tinnies mate, been well oiled for the last few hours pre-match and during, but when Arsenal scored that 3rd goal I was gutted .......... now started on the Vodka [img]images/graemlins/laugh.gif[/img]

Andiroo [img]images/graemlins/062802drink_prv.gif[/img]

[TimJMS]

What you need, what you really, really need are cone shaped air deflectors bolted to the outside of the alloys deflecting air inwards, and through the spokes to the rotors. Just like Audi America did when it went racing with the 200 turbos. Fresh, cool air. And lots of it [img]images/graemlins/thumbs.gif[/img]

clickety click

[Andiroo]

Very good point Tim [img]images/graemlins/thumbs.gif[/img] although they do look a bit pants [img]images/graemlins/tongue.gif[/img]

mmmmmmm...............

Andiroo

[dog]

Thanks for the info, I am waiting to see the outcome. I must admit that my car have to be 100% reliable and I can't have it off the road much at all. (It was a tough 3 weeks while being repaired after the wheels got stolen)I would like to have a lt of extra power when i need it (occasionally only as traffic sucks in Sydney) without blowing the engine or shortening it's life significantly.

[wazza]

What you need, what you really, really need are cone shaped air deflectors bolted to the outside of the alloys deflecting air inwards, and through the spokes to the rotors. Just like Audi America did when it went racing with the 200 turbos. Fresh, cool air. And lots of it [img]images/graemlins/thumbs.gif[/img]

clickety click

Hmmmmm. I wonder who used to work with that Audi team?

[TimJMS]

Spill the beans, Paul! (Although I can guess)

Andy. Yes they look pants but what do we care if they do the job on a trackday? Take 'em in the boot. Studs out. Deflectors on. Studs back in. Sorted.
[img]images/graemlins/thumbs.gif[/img]
Karl? [img]images/graemlins/grin.gif[/img]

[Bushy]

What you need, what you really, really need are cone shaped air deflectors bolted to the outside of the alloys deflecting air inwards, and through the spokes to the rotors. Just like Audi America did when it went racing with the 200 turbos. Fresh, cool air. And lots of it [img]images/graemlins/thumbs.gif[/img]

clickety click

I have ordered some of these, hope to fit them when I fit the 6 pots

porshe duct to brakes

[TarmacTerrorist]

There the boys! Direct cooling to the brake areas and not just filling the arches with more air (more drag?), these have got to be a much better alternative to cutting dirty great holes in the arches and and be guaranteed that the extra air your forcing in there is going where you want it to.

Vinny.

[Andiroo]

Will u have them fitted for Hockenheim Bushy? Looks a very sound and practical solution [img]images/graemlins/thumbs.gif[/img]

Andiroo