Ok, so I sold the car but I can still give you guys some pointers and tips on how to fit a big Forge core with 2.5" outlets, keeping fogs and without cutting your bumper/grille to pieces. I'm pretty sure though that my system kept things cooler than a standard 2" Forge (with the OE squeezed tube with the MAP sensor). I think the larger/better Dahlbäck intake also worked down the temp (to some degree), but that's my opinion, I can't prove it though.
At least I knew that particular FMIC setup worked well on other cars so I wanted that...How much it was better I honestly don't know...but it worked like it should and I didn't blow any hoses off either even though I had plain ol' jubilee's...and had a remapped engine (1.58 peek).
First of all; fitting a fairly large Forge FMIC (see this page
http://www.turbopower.no/intercooler.html, item no. FMINTE08) was a pain in the ***. Choosing 2.5" in/out of the cooler and 2.5" pipes all the way from the Turbo hot pipe to the intake manifold, we knew it could be done and still maintain a OE looking car WITH foggies but the setback was the time we spent trying out different things and solutions. Jesus I wouldn't do it ever again to be honest.
Others have copied "my/our" setup and even they had a tough job dooing it right too.
The biggest problem were obviously to route the pipes so that they were tucked in nice and TIGHT. You have to use two times 90 degrees at each side right away coming in/out of the cooler. You have to get the pipes inwards to the engine before you go sideways towards the wheels/fogs. You have to cut out a big chunk of plastic from each side of the big front plastic piece..No problem tho, really who needs it? It has no functions what so ever...
We had to manufacture new brackets for the foglights. We had to turn the "lid" holding the fog light switch (the thing you open to change the bulps) on the right foglight (your drivers side) so that the switch/contact were turned 180 degrees...that thing is huge and totally in the way. Brackets were a nightmare to do because the material we had at hand were crap. But they finally came in place and were much better fitted than OE (50% of the brackets were broken on my car) when we were finished...
We had to grind down 0.5cm from the backside of the grille surroundings for the fogs. This was because the pipes stuck out a little bit in that area even though the cooler were placed as low as the bumper allowed and so close to the radiator that we could manage. The grille surroundings build inwards the bumper when they are fitted so a dremmel come in handy...No biggie though and you couldn't see it unless you stuck your head in there!
It took forever to adjust the pipes (going through numerous variations on pipelength and 45/90 degree bends) but that's obvious having read this thread
We had to secure the bumper to the undertray with new and stronger screws...again not visible to the eye and not important really...
That's it lads...get to work and fit your large Forge/AH coler with those big 2.5" bore pipes...I think "my" setup is the largest kit possible on a S3. If it's that much better than Forge's own kit...I couldn't tell