GOLFMK8
GOLFMK7
GOLFMK6
GOLFMKV

How to retro-fit skid trays, aerodynamic under trays, & stone guards to a MK7 Golf

golfdave

Autocross Champion
Location
Scotland (U.K.)
Car(s)
Mk7 Golf GT Estate
GolfDave many thanks for your efforts in researching and posting your troubles of doing this!

At the time I secured my Golf Estate, my first intentions were to do exactly this to the underside as I know the extent in which a fully(ish) panelled underbody can affect the way in which a car handles, performs.....
Once I received the car I started your thread and bought the lot, including claiming on the warranty the tow hitch cover and fitted them within the first few weeks of the car being in my hands.

Apologies if I'm repeating a question asked previously but to your knowledge is there a mid section panel for the tunnel between the two cross members?
Many thanks
Connor

Glad the info has been of help!

I have searched high & low & there is nothing for between the rear of the front exhaust tunnel cover & the fuel tank.
 

CLDuckworth1

Ready to race!
Location
Manchester
Dare i say it.... I've made my own

I dont do things by halves so I decided to measure things up and create a panel.
The main sheet is 4mm HIPS and then wrapped it in 30micron foil and again in 100micron foil.

For the main heat shield I used stamped aluminium to insulate the panel from the heat and the final product is certainly fit for purpose.

https://plus.google.com/u/0/photos/...m/6395059377803429953?authkey=CNn7sK7LutHP0QE

It runs from the mid front tunnel brace to just past the mid rear tunnel brace, of which it is bolted to. The other holes you can see are for the threaded bolts that are welded to the underbody which secures it, sandwiching it between the chassis and the large underside panels.

Thanks to your help, the car is *fully* paneled other than the tyre well and rear exhaust silencer.



Aluminium sheet - http://www.diy.com/departments/aluminium-panel-l1m-w500mm-t1mm/254163_BQ.prd
 

CLDuckworth1

Ready to race!
Location
Manchester
The only other way to cover that mid section would be to get the eGolf 5QE825229B under tray which is £93* from parts and then cut it down on each side to fit.
It uses the same mounting bolts I mentioned that are welded to the body
 

golfdave

Autocross Champion
Location
Scotland (U.K.)
Car(s)
Mk7 Golf GT Estate
Dare i say it.... I've made my own

It runs from the mid front tunnel brace to just past the mid rear tunnel brace, of which it is bolted to. The other holes you can see are for the threaded bolts that are welded to the underbody which secures it, sandwiching it between the chassis and the large underside panels.

Thanks to your help, the car is *fully* paneled other than the tyre well and rear exhaust silencer.

The only other way to cover that mid section would be to get the eGolf 5QE825229B under tray which is £93* from parts and then cut it down on each side to fit.
It uses the same mounting bolts I mentioned that are welded to the body

I looked at those pictures.....;)

I was thinking of doing similar, but decided against it as trying to do OEM...

Also I do not want to cover over the mid silencer that I have (between the brackets) as I do not want to cook it & the metal work behind..even with the foil! Just I do "hot" 2hr drives...:D

Same reason why I decided against the e-golf parts....
 

CLDuckworth1

Ready to race!
Location
Manchester
Yeah i can fully understand and thats why i was thinking of getting the skid tray with the gear box cooling holes
Hopefully it would add to the positive air pressure inside the engine bay, forcing its way out more down the tunnel, maybe...
 

golfdave

Autocross Champion
Location
Scotland (U.K.)
Car(s)
Mk7 Golf GT Estate
Yeah i can fully understand and thats why i was thinking of getting the skid tray with the gear box cooling holes
Hopefully it would add to the positive air pressure inside the engine bay, forcing its way out more down the tunnel, maybe...

Hmmm,

good thinking there...:cool:
 
Location
St. Olaf
Yeah i can fully understand and thats why i was thinking of getting the skid tray with the gear box cooling holes
Hopefully it would add to the positive air pressure inside the engine bay, forcing its way out more down the tunnel, maybe...
The lower engine bay cover lowers engine bay pressure and that's a good thing for
cooling, since the lower engine bay pressure helps for a bigger pressure difference
between in front of the radiator and back of it, increasing through-radiator air flow.
With the lower cover, the only way for any air to enter the enigine bay is passing the
radiator. Less air leaks, improved efficiency.
 

golfdave

Autocross Champion
Location
Scotland (U.K.)
Car(s)
Mk7 Golf GT Estate
With the lower cover, the only way for any air to enter the enigine bay is passing the
radiator. Less air leaks, improved efficiency.

errrr...no!

High entry point is the slam panel, left hand side fully open, next to the air intake for the engine. I know as loads of dirty road spray gets on the left side of engine. The VW GRP skid tray has two NACA ducts in it which scoop air up & into the engine bay & mainly directed at the gearbox area. The only easy way out for this is either via the driveshaft exit holes in the wheel arch, or backwards down along the exhaust tunnel.
 
Location
St. Olaf
Right, there's one vent for the generator and there are two for the gearbox.
Quite negligible in this context, as the skidtrays and covers still reduce engine
bay pressure thus increase radiator airflow and that's the point. Self-evidently
an automotive engine bay can't be hermetically sealed.
 

golfdave

Autocross Champion
Location
Scotland (U.K.)
Car(s)
Mk7 Golf GT Estate
Right, there's one vent for the generator and there are two for the gearbox.
Quite negligible in this context, as the skidtrays and covers still reduce engine
bay pressure thus increase radiator airflow and that's the point. Self-evidently
an automotive engine bay can't be hermetically sealed.

The whole point of what "CLDUCK" was trying to state is the fact if you fit the full engine skid tray & then cover up the whole length of the exhaust tunnel, that as air is entering the engine bay via the Naca ducts & slam panel that it will eventually make it's way down & along the exhaust tunnel...the rear opening just before the fuel tank will be under a small amount of negative (suction) pressure, therefore he hopes that this will help pull the air flow down along the exhaust tunnel...thus cooling the exhaust silencer

From what I remember doing windflow stuff I have no reason to doubt it..
 

CLDuckworth1

Ready to race!
Location
Manchester
Apologies gentlemen ive for some reason not seen any notifications of the quotes and chat - i'll get onto that once ive posted this :)

Great to get ideas flowing on this subject as ive had all these thoughts with that voice in your head that argues back... im mentally stable

Im really wanting to get the car up in the air now that all the panneling is done and to check for possible signs of excessive heat in that area. Once I do, I will take pictures and share them including the panel I have created.
Ive got a 400mile journey to do next weekend coming back from Hastings, of which will be a great test for heat soak into the cabin floor. Im hoping at somepoint in the journey it will run a DPF Re-gen.

To reiterate what Dave has said on a previous subject, the car certainly does feel a considerable amount more solid/planted at speed as opposed to the rear of the car being jittery.
"I can also report that the rear of the car feels less “light” & more “planted” & stable when going around fast corners.."

Great to have this debate with like minded people
Best regards
Connor
 

flutie98

New member
Location
Upstate NY
Quick question regarding the aero trays.

With part 3Q0825236 there seems to be multiple revisions available

3Q0825236, 3Q0825236-C, 3Q0825236-D

Anyone know the difference?
 

golfdave

Autocross Champion
Location
Scotland (U.K.)
Car(s)
Mk7 Golf GT Estate
Quick question regarding the aero trays.

With part 3Q0825236 there seems to be multiple revisions available

3Q0825236, 3Q0825236-C, 3Q0825236-D

Anyone know the difference?

No, it could be a totally different part, or just the latest build version...double check with ETKA & see what it says
 

surfstar

Ready to race!
Location
Cali
Quick question regarding the aero trays.

With part 3Q0825236 there seems to be multiple revisions available

3Q0825236, 3Q0825236-C, 3Q0825236-D

Anyone know the difference?

If ordering one, you need to see a photo of the actual part.
In my searching of images, it seems that they would come with vent holes, no holes, insulation, etc. Didn't seem to match to any specific p/n revision, either.

I went by price, and ended up with a 5Q0825236, a non-vented shield from an Audi TDI (I think). I have a 5 speed manual and 1.8 TSI, and do not drive the car hard, so I was okay with not having bottom engine vents. My oil temps are up 2-3 degrees, on average, but still below stock USA GTI levels.
 

Flanbix

New member
Location
Grenoble
I had my under tray replaced by the VW garage because the previous VW garage which repaired my damaged GTD did not replaced it.
I was wondering if there was a fondamental difference between the old one (5Q0825236)



And the new one (5Q0825236Q)




Obviously there is extra vent now, for the gearbox it seems. I guess that is good. But does it make the engine bay more prone to dirt too and more vulnerable to rock and such.
I guess that is fine like that, I was just surprise when I got the car back from the garage to see that the parts are differents. I did not know that was such a variety of model for such a "simple" part! :confused:
 
Top