Speed Engineering - Mk7 GTI Brake Duct Kit Review

[bobivy1234]

Hi All, always had issues with my brakes out on track and was always looking for a ducting solution. While I wished I could go through the fog lights, few groups out there are building kits focused on under-car airflow as an improvement to the RS3 deflectors. I picked up the Speed Engineering Mk7 GTI brake kit from the German-based company for around $350 all-in to test this out before upcoming track days. I know others like CJM are making these but they aren't ready just yet:

First impressions are good and shipping was crazy fast from Germany as I ordered on Wednesday and got them to NC on Monday. The scoops are 3d printed but very good quality, the backing plates are metal and intentionally shaped to protect the ball joints while still trimmed compared to the stock heat shields. They sent the brake tubing as one piece so I'll need to cut them and tape up the ends before install.

Pics of unboxing attached, will update this during install as well as track testing next week at VIR with TrackAdvantage. Currently running Macan Brembo 4-piston brakes on the fronts with ECS 2-piece semi-float slotted rotors and PFC08 brake pads with titanium shims.

Product link for reference: https://www.speedengineering.de/pro...PYwwguwfvVX3YK_X25nxsp0epsB6N66CmflNmQzqhk-ng

 

[reverend_sean]

Awesome!

 

[steddy2112]

Interested to see how this fits up, the tubing isn't cheap so make sure you measure 8 times and cut once lol.

Oh and following the link you posted shows where the "intakes" go. This is a pretty slick kit and honestly 350 is not a bad price if it fits up well.

 

[gboticus]

Really interesting looking kit. I had been watching CJM's development with great interest.

I do worry though that the duct mouth is quite tall and would have all sorts of clearance issues on a really low ride height? Looking forward to install pics!

 

[SouthFL_Mk7.5]

Subscribing. Very interested to see final install.

 

[steddy2112]

Really interesting looking kit. I had been watching CJM's development with great interest.

I do worry though that the duct mouth is quite tall and would have all sorts of clearance issues on a really low ride height? Looking forward to install pics!

Would only be a clearance issue for a little bit lol but really at the track that shouldn't be too terrible of an issue.

The real issue is for lazy people like me who won't take them off when on the street because I am fat and crawling under a car is pretty low on the to do list when you're lazy AND fat

 

[bobivy1234]

Would only be a clearance issue for a little bit lol but really at the track that shouldn't be too terrible of an issue.

The real issue is for lazy people like me who won't take them off when on the street because I am fat and crawling under a car is pretty low on the to do list when you're lazy AND fat

Still have a few other things to knock about before installing these but the good news is that you could just block it off pretty easily after the track or keep them on there for full-time use. Really shouldn't affect steering outside of full lock. They direct air almost directly to where the current RS3 deflectors sit on my car.

 

[gboticus]

Would only be a clearance issue for a little bit lol but really at the track that shouldn't be too terrible of an issue.

The real issue is for lazy people like me who won't take them off when on the street because I am fat and crawling under a car is pretty low on the to do list when you're lazy AND fat

lol fair points. I would definitely be in the lazy category and not want to remove the ducts between track days: just too much work. Maybe block or remove the hoses when I swap my street tires on, but not remove the ducting heh.

 

[DerHase]

How big are the ducts?

Look into what Vorshlag does with their S550 Mustangs to keep the brakes cool. In a nut shell: airflow through ducts is really terrible.

Especially if they're undersized (which according to my eye-crometer those are maybe 2in or 2.5? Those are barely adequate for a Miata).

The Vorshlag air scoops were more effective than a 4in duct (which will flow somewhere around 2.5 times more air than a 2.5 in hose for comparison).

I don't doubt that they'll do SOMETHING... but are you doing anything to actually test (measure) temperatures before vs after?

For reference:
https://vorshlag-store.com/products/vorshlag-s550-brake-cooling-deflector-kit


edit: Don't take my skepticism personally... but the lack of ACTUAL R&D on this platform with real data is infuriating in general.

 

[bobivy1234]

How big are the ducts?

Look into what Vorshlag does with their S550 Mustangs to keep the brakes cool. In a nut shell: airflow through ducts is really terrible.

Especially if they're undersized (which according to my eye-crometer those are maybe 2in or 2.5? Those are barely adequate for a Miata).

The Vorshlag air scoops were more effective than a 4in duct (which will flow somewhere around 2.5 times more air than a 2.5 in hose for comparison).

I don't doubt that they'll do SOMETHING... but are you doing anything to actually test (measure) temperatures before vs after?

For reference:
https://vorshlag-store.com/products/vorshlag-s550-brake-cooling-deflector-kit


edit: Don't take my skepticism personally... but the lack of ACTUAL R&D on this platform with real data is infuriating in general.

Thanks and appreciate the info, I'm running the RS3 deflectors now but have not rigged up anything to test temps yet so maybe I'll grab some caliper temp strips or grab a heat gun for after sessions or something. I'll measure the inlet size later tonight and update. Suggestions on testing are welcome also.

 

[DerHase]

Thanks and appreciate the info, I'm running the RS3 deflectors now but have not rigged up anything to test temps yet so maybe I'll grab some caliper temp strips or grab a heat gun for after sessions or something. I'll measure the inlet size later tonight and update. Suggestions on testing are welcome also.

Genesis temperature changing paint
This stuff is pricy but is the only thing I'm aware of that will indicate such a wide range of temperatures. Most single temperature changing paint will be about $40/tiny bottle and you'd want 3-4 of them at least. Downside is the stuff is pricy.

IR temp gun from Amazon
You can try using an IR thermometer, but the rotors themselves will exceed 1000F on track (which most temp guns won't read). I did actually just buy this from Amazon... but no idea how well it'll actually work. If my rotors get to 2400F I've got other problems.

I would block off both brake ducts with masking tape and do 3-4 hard laps, then come into the pits to have someone waiting to check the front rotor temperatures, yank the tape off the brake ducts and go back out for another 3-4 laps again at full pace, then recheck again immediately. No cool down laps, etc can be done prior to checking both times. Then go back out and goof around for whatever time remains, do a cool down lap before parking the car so you don't crack a rotor.

You can also check stuff like the brake calipers themselves, etc too. When using an IR thermometer you need to make sure you're not shooting it too far away as the further away you get, the larger area it is sampling and will "average out" over said area.

 

[scrllock]

How big are the ducts?

Look into what Vorshlag does with their S550 Mustangs to keep the brakes cool. In a nut shell: airflow through ducts is really terrible.

Especially if they're undersized (which according to my eye-crometer those are maybe 2in or 2.5? Those are barely adequate for a Miata).

The Vorshlag air scoops were more effective than a 4in duct (which will flow somewhere around 2.5 times more air than a 2.5 in hose for comparison).

I don't doubt that they'll do SOMETHING... but are you doing anything to actually test (measure) temperatures before vs after?

For reference:
https://vorshlag-store.com/products/vorshlag-s550-brake-cooling-deflector-kit


edit: Don't take my skepticism personally... but the lack of ACTUAL R&D on this platform with real data is infuriating in general.

tbh i'd be pretty skeptical anyone needs these outside of endurance racing (where you'd have other heat issues on these cars). if they _do_ work, overcooling can crack rotors, too.
IMO the full RS3 setup is a great option with both the deflectors as well as the vented shields.