Originally Posted by ucla bruin

Theory: Injen CAI suffocates the filters because the poor filter location. No access to air.

Test: I dynoed my car with Injen CAI with the bumper off so the filters can breathe "fresh" air. Then dynoed it again with the bumper on.

Result: The difference was 1-2hp.

Note: You can open up vents and stuff to expose "fresh" air to the filters but risk the chance of more road debris + water to get to your filter. IMHO, it is not worth that extra 1-2hp.

Another note: I brought up the question about suffocating the filters to Injen's R&D director. What I gathered is that the filters are not suffocated because you can pull air from all around. From the lower + upper grill and the hole on the bottom near the under carriage (check it out). Fact is there's cool air all around and gets pulled when needed. The filter doesn't need to be blasted with open air, which if done incorrectly, can produce a dangerous AF ratio due to leaning. Also, the filters are located furthest away from the injen or any other heat source.


The intuitive but common misconception is that the filters need to be exposed, out in the open for it to get cool air or fresh air. But this is simply not true.

Originally Posted by yogregb

Well I was going to leave this one be......but... I have to disagree Danny, please know I respect your opinion. I think what your forgetting is that on the dyno, your car is not at speed, therefore your discounting the ram air effect, which makes this intake system perform at peak, thus giving you more then 2 hp difference. I don't know about your car ,but My 09' model has a plastic partition in that area blocking off the lower grill. Your right, there is a small drain hole at the bottom of the plastic wheel liner, but that's it on MY car, I know, I've been in there enough! And I agree the filters are farther away from eng heat in general. The bottom line for me, is, I know I improved my intake system simply by giving it a 2 1/2 vent and as far as af ratio, that's the MAF sensors job. Overall I think this intake is a worthwhile mod, just for looks and sound, let alone hp gains..my 2 cents...
Sooo... when are you going to do my headlights and I'll do your fogs??

Originally Posted by yogregb

I think what your forgetting is that on the dyno, your car is not at speed, therefore your discounting the ram air effect, which makes this intake system perform at peak, thus giving you more then 2 hp difference. I don't know about your car ,but My 09' model has a plastic partition in that area blocking off the lower grill.

Originally Posted by yogregb

Uhh... pull cold air from exactly where, because that area where the filter is sealed off from the front lower and upper grills

Originally Posted by hispeed-lowdrag

A dyno would be worthless if you couldn't simulate "at speed." that's why every single dyno uses a huge blower to push air through the front of the car...so no, that wasn't forgotten.

Also, I know for a fact that middle grille is completely open, there's no plastic sealing it off. There's mesh for the bottom grille, but it's completely open from front to back.

Not trying to be a d1ck, just saying that plenty of fresh air circulates down there

Originally Posted by franky2222

theres maybe is a diff in the sport and non sport bumper????Q8Y how hard is it to remove those plastic things you speak of and does the sport bumper have them too????

Originally Posted by efuseakay

It's not air tight.

Originally Posted by Q8y_drifter

Actually the sides are sealed off to divert air towards the radiator and P/S cooler. take a look into the lower grille in the middle and look inside towards the left and right side. There's a plastic piece on each side that blocks air from entering the sides, since there's nothing to cool anyway. I actually took them off, redyno'd and made another 4whp. That's before I even drilled holes into the fake mesh on the journey bumper. I dunno how accurate that is but I made several runs before and after and that was the difference between each average. I have the Injen CAI btw.

EDIT: Look at the pics voltic posted on post #18. The first pic shows the 2 plastic i dunno what you call them on each side. When the bumper is reinstalled, those pieces block a lot of the air that is meant to go thru from the bottom center grille.