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Old 07-16-2011, 10:08 PM   #1
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Factory Air Box vs. Short Ram testing

So I was curious about the actual numbers comparing the factory bread box, to the much put down short ram intake set up. I have read countless arguments from those that say the short ram just sucks hot air and is useless, but never had any numbers to prove their point. So here you go.

I'll start by saying that the factory air box is as close to a true cold air intake as you're going to get. The air that feeds it is drawn from in front of the radiator, and the box itself is as close to the intake as you can get. No pipes running down the side of the engine next to the trans or what have you. So I'm going to consider this a CAI to SRI comparison. You may disagree, and that's fine with me. But I have numbers. :)

The constants:
-84 degrees ambient temp. Partly sunny. No accessories on.
-Wide open throttle until reaching cruising speed of 60mph.
-5min cruise at 60mph maintained.
-Factory filter.

The variable:
-With factory box, without factory box. (completely removed)

I began by removing the air line that feed the valve cover. Then inserted the probe from my Fluke meter, and taped closed. The probe was monitoring the air from behind the MAF sensor. I thought this would be the best area to gather real numbers.

I then went for my drive. The most consistent reading came to 89.9 degrees at 60 mph maintained over 5 mins.

I returned home. Put the complete factory set up back together and went for my second drive in the same manner.

88.3 degrees

A difference of 1.6 degrees isn't quite that much to cause all of the complaining about short intakes sucking hot air. At least not in my "daily driver" book.

In my looking around with the air box removed. I notice there really isn't any place at all for fresh air to get in. Imagining where the CAI (once released) would draw from, the only place I could think of would be to remove the backing to the driver side triangular part of the grille. I can only imagine the issue with water now flooding into the engine compartment. Especially with the low air dam still on.

I've considered drilling holes in the plate, and purchasing a 90 degree elbow to point my filter downward, remove the box completely, and fabricate a stainless steel bracket to hold the filter/MAF combo. I'll take pics when it's done. :)

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