Brake ducts?

[RJKflyer]

I've seen a few posts around the place about high rear brake temps. I too have notice this, although I can't say it's a problem. I'm sure PTV adds to the rear heat load.

However, have also seen a number of posts where folks have changed the stock rear plastic ducts (on the swing arms) to GT3 ones, which appear to e more contoured. Saw one post claiming a material impact on (in particular) caliper temps.

It appears to be a clip off-clip on sort of mod. If I've read PET correctly, the TT parts are 997 341 483 01 /L /R and the GT3 ones K 997 341 483 92 /L /R.

Anyone done this?

 

[ralphmusic]

At a very hot Silverstone PCGB track day recently I seemed to have turned my front disks blue and accelerated the development of cracks. The front and rear discs vents were blocked with accumulated brake dust. So as all the wheels were off and the fronts getting to the end of their life I had new front disks and the rears cleaned out. Cost - don't ask.. The car has Pagid Yellow pads all round.

Perhaps ensuring disk vents are not blocked would be a first simple step?

 

[spyderman]

By coincidence, I'm currently in the process of fitting larger ducts to my 986 to improve cooling for track days. I'm going for the 997 GT3 (road) ones but the Cup ones are even larger - and more expensive, because they're two-part. Unfortunately they're so large I think the average speed ramp would ruin them - and my town is full of them! I ordered mine from the US, but the 997 ones are actually pretty cheap via your OPC - about £15 each.

I was sent this image by a very helpful chap on 911uk.com - it shows, from top to bottom:
986 standard
997 GT3 997 341 483/484 92 spoiler (this is what I've ordered)
996 GT3RS 996 341 117/118 92 spoiler (similar size to Cup)

You can also fit GT3 wheel arch liners which allow air that's already passed through the condensers and rads onto the discs. Apparently these are about £85 each.

Regards the cross drills - certainly unblocking them would help but after a few laps, they'll be blocked again. If you think the discs aren't up to the task, its time to switch to slotted discs.

 

[ralphmusic]

I guess I better get out and have some fun filling them again, thanks for the thought of the different type. I wonder if others have experience of the two types?

 

[RJKflyer]

Sorry if I have missed an obvious point re the GT3 Cup ones, but if they too are fitted to the swing arm, then why would ground clearance be an issue?

(One thing i think may have read is that the GT3 ones are a simple swap, the Cup ones need part of the backing plate cut away to be worthwhile?)

 

[spyderman]

ORIGINAL: RJKflyer

Sorry if I have missed an obvious point re the GT3 Cup ones, but if they too are fitted to the swing arm, then why would ground clearance be an issue?

Er, because they're bigger?

 

[RJKflyer]

Ah yes I now see that they hang down lower from the arm - my original logic was that as the arm moved, it wasn't in principle impacting ground clearance.

So, anyone done this and what beneficial effect?

 

[jbm]

I fitted a set of rear brake ducts from a Gen 2 997 GT3 to my Gen 1 997 GT3 - it was a pretty easy DIY job although you do have to trim some of the brake shield to allow the air access to the disc. I had no problem with ground clearance on the ducts and they really seemed to help with cooling on the track - it seems a popular mod in the US.

 

[spyderman]

Just got an email back from FrazerPart with an excellent price for the 997 GT3 front ducts.

web:- http://www.frazerpart.com
email:- info@frazerpart.com
Tel. +44 (0)151 644 6433, +44 (0)7958 697333