It all started with Howard (yell03) not wanting to get his K&N filter wet.
He posted that the stock rain cover could be installed backwards and the hood could be closed.

Taking his brilliant observation one step further, I saw it as a basis to create a cold/fresh air plenum to feed aftermarket filters such as K&N, Halltech, and SLP BW

Below is a rain cover mod for a SLP, but concept same and slight mod may be needed to the template for Halltech and K&N.

1) CUT OUT FRONT FASCIA EXTENSION ALA HALLTECH CAI.

The result will be an opening behind your grille on either side that feeds the area where the air filter sits.

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2) NEXT CUT THE FRONT EDGE OF THE EXISTING RAIN SHIELD USING THE TEMPLATE BELOW

Note that the front edge will become the edge toward the engine bay once you reverse it.

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3) The end result will look like this.


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It appears that the hood insulator compresses against the front edge of the modified rain shield giving it a seal. Not sure if I want to fabricate sides out of PVC or use gasketing to create a fresh/cold air plenum. Possibly a combination of both materials.

So far, very easy DIY, if no other mod is made, this install will help in directing air to the filter and of course keep it dry !!!

No thanks for your being lazy Howard, but much thanks for thinking !!!

Ed A.

 

VERY WELL DONE!!!

Howard

 

 

Sweet

 

YOU SONS A B^%%$CH'S are really trying to get me to do manual labor on my car and save some money,aren't you?!!First Howard,now this....what's this world coming to??? Nice job!!

 

jesse12804 -

I even pulled out the shop vac and vacuumed out where we drilled the holes yesterday

RBYCC -

I am still trying to decide on doing your mod of the rain shield.

It will block water which is a plus, but not as necessary as I originally thought.

It should keep cooler under the car air going to the filter, another +.

My only question is:

There is some airflow that comes through the hood seal.....

Do you think cutting off this between the hood airflow is outweighed by the two advantages above????

Also, How did you cut the front fascia?
Was it still on the car?

Howard

 

Howard

I doubt that you get any air through the leading edge of the hood opening as it is a laminar flow which would go right over the gap and to the windshield area. If you got flow at that point it would create turbulence which is the enemy of a good aerodynamic design.

I was not concerned about blocking water as the amount of water that you might get when washing or opening the hood when wet is minimal. Additionally your filter element on the K&N, SLP, Halltech are all washable fabric, so no harm if wet.

From what I can see the stock airflow comes from beneath the vehicle in the radiator area and from the engine bay.

Cutting open the front fascia extension, which must be removed from the vehicle to do so, allows much more outside air to enter into the filter area.
That seems to be the reason why Halltech offered the CAI fascia extension.

I'm trying to use the reverse rainshield as the basis to create a plenum area for the filter intake.
It appears that the hood insulator now seals the front of the plenum.
I haven't decided how to seal the back or engine bay side of the newly defined plenum.
Easiest way would be to gauge the distance between the radiator cover and hood insulator when the hood is closed and install a foam gasket.

This will create a plenum that would prevent engine bay heated air from entering the filter.

I'll post some pix after I road test what I already did to see if I've created any problems !!!

Ed A.

 

Nice, start a buisness & sell to forum guys.....

 

I guess i could go out to the garage and look, but its dark, so where is this stock rain cover? Does it extend under the front normally, and thats why I dont remeber seeing it?

 

The rain guard is the plastic piece that sits on top of your stock airbox.

It just sort of hangs there.

You can't miss it.

Howard

 

Oh, thats right, that came off when i swapped out the intake to a halltech. thanks.

 

jsk96z28 -

Did you notice any major difference after the Halltech???

I did the K&N aircharger (same thing as Halltech) and can't say for sure if I gained anything.

Now I drilled holes in the lower fascia to bring cooler air up to the filter, but I still can't say for sure?

I think my Butt-o-meter is broken

Howard

 

Well, not a whole lot per my g-tech, but I wasn't expecting more than 10hp anyway (got 8hp), which is what I got. Plus, I just enjoy the sound of the CAI's over stock. I'll have to check out this cold ait mod and see if that makes any change.

 

Based on one of your threads I went and got the K & N and I gotta say the car feels much better. haven't done a tune or any other performance mods, but for what I paid...I'm very pleased. Thank you, Andy

 

Andy -

Glad to hear you like it.

If you do what I did and drill holes for cold air, don't hack it like I did.

Plan it out ahead of time.

I might try to salvage it if I can neatly cut it completely out, but

most likely I am gonna order a new front fascia for $23 shipped and cut it out of the car.

I am not looking forward to the install though

Howard