<center><img src="http://pictureposter.audiworld.com/5373/front_ic_air_flow.jpg"></center><p>Trying to decide if cutting open a bigger inlet hole on the passenger side front air damn (if your a 225 you have one on each side) is a good idea.
-Item #1 (next to speckeled arrow) in the pic is the 'extra' plastic piece in question.
-Item #2 is the actual hole that leads directly to the IC.
-Item #3 is front air dam from bottom center grill


At first, it seemed logical to remove plastic piece #1 which obstructs part of the front side air damn, keeping extra cool air from reaching the IC. Then I started thinking that piece #1 must have been put there for a reason, and it doesn't seem cosmetic because you can't see it from the outside. I then noticed the front air 'dam' that is placed on the left hand side of the front lower center air grill on the bottom. It looks as though the air is swept across from the center air grill towards the side IC and maybe, just maybe, piece #3 was added to help capture the air that swept across from the center (indicated by my speckeled arrow.)

What do you guys think?

pic used and mutilated without permission from SwifTT, lets not start another one of those threads

 

What is the trade off in cooling effectiveness of volume vs. velocity? (If you "open" up the flow will the decreased velocity matter?)

Just thinking . . .. (But good way to attack - more power comes from improving intake/exhaust efficiency or -in the case of i/c turbos - more cooling of the intake charge.)

 

FREE TO BE USED!

I was looking at the extra piece that directs the air into the passenger side IC, I'm pretty sure its there for a reason, but I still can't figure what. However, I removed the piece from the driver side of the grill(no IC on the 180), now cool air is going into the engine bay and for the stock air box. I think we need a bigger IC because our factory one just isn't doing too much of a job

 

I removed mine right after I got the car with no perceived benefit or ill effects.

 

what does cool air mean?(temps) and how does it help. how much air flow (not sure how to measure that) do you need? And how much performance increase or what value does this add?

just your non mechanical person not aware of what IC is for asking.

 

IC = Intercooler (think of it as an 'air radiator' cooling hot engine intake from turbo)

 

thereby creating more turbo lag. However, just because the housing is larger (Forge) doesn't mean that the internal piping is greater in volume. It could be even smaller with more space in between for increased external air flow for increased cooling efficiency. Time for a dissection of the Forge.

 

Just fill them with water and measure what goes in. Volume, ya know. Shake&tap to get air out...

 

restrictive, then the air flow dynamics could potentially overcome a marginally greater volumed IC.

 

When I first looked at the intercooler setup I was really baffled. It looked like it could be improved. But after some serious consideration this is what I think now.

1) The air does not need to blast straight thru the IC. What the IC depends upon is that there is a pressure difference between the air on the entry and exit of the IC.

2) The piece that you noted as an air dam is an air dam! It not only serves to direct some positive pressure to the front of the IC, but it also lowers the pressure under the whole car, and I'll bet it indirectly lowers the pressure on the back side of the IC.

3) I'm not convinced that the "extra" piece in your photo does anything useful for the IC. I'm guessing that it is purely cosmetic - when the TT is viewed from the front you can't really see the shiny IC in the lower cheek. But I also don't think that it impedes the flow to the IC. These are just my guesses.

4) I've observed some sophisticated air cooled engines on aircraft that include oil coolers and intercoolers, and it amazes me how little cooling inlet surface area there is necessary for such a large cooling job. I've seen 300HP motors cooled with just two 3 inch diameter ducts. The trick employed by the aircraft folks is that the ducts feed a chamber referred to as the plenum. And they go to great pain to be sure that NO air leaks from the plenum except thru the parts to be cooled. If there is a small leak in this setup it acts like a short circuit and lowers the pressure in the plenum drastically.

4) I respect the engineering that went into the TT. I don't see anything that was thrown together half baked. The designers went to great length to get the specific horse power that they achieved. I would never mess with it, but that is just my opinion.