That looks like its a pop charger air filter eclosed in the Stillen Cold Air Intake box... I think you can make out stillen writtin on the air box... i have it thats why, by the way does the pop charger air filter flow better than the stillen filter?

2003 Laser Red 6 spd coupe
Stillen Intake w\ Z tube
Kinetix HF Cats & Plenum
U/R Crank pulley
w\ nav...

 

That's right! DaveO told me once that he bought the
pop-charger filter and fit it to his Stillen. I am interested in
the extra air entrance DaveO has added. Please tell us more
about it!

03 5AT Sedan, sunroof, splashguards, HKS muffler,
14 wire Grounding kit, Z Duct, Stillen HF/AB
Underbody rear diffusers, Drilled alum pedals,
Stillen sway bars S/H. Sport Tuned Suspension

 

Chuck,

I have no way of knowing if one air filter flows better than the other. It would probably take an air flow bench to tell the difference. I do know that the Popcharger filter is slightly shorter, open ended and it has an internal air flow device.


Guys,

I cut an opening in the radiator core support to allow air flow into the end of the air filter. Based on dirt and bugs, it seems to be working. I did this based on my non-scientific, subjective analysis of several G35 flat panel and conical air filter "dirt patterns" and bug accumulations. Why? Because I'm not convinced the "Power Duct" does very much when the hood is closed.

If things go well, a friend will do some tests with a digital manometer which should help to resolve this issue.


DaveO
03 G35 AT Sedan / DP / Willow / Premium / Sport / Aero / Mods / 262 & 260.8

361361-Stillen - JWT Filter Elements.JPG

 

When you measure the differential pressure across the air filters [with an accurate manometer] at the flow the engine can injest [limited by 214 cubic inches] and outside barometric pressure, you see from best to worse is under 1% change in air flow.

Sure a lot of work for less than 3 HP over oem.

 

Ebay is a great place to buy Dwyer Minhelic and Magnahelic small handheld dial manometers in 0-3, 0-10, 0-30 inches of water column for under $30 each ~~15-$20.

Prior to MAF the worst case will be under 5", after MAF under 15", in plenum after TB under 20" at WOT at 6500 rpm.

SAE flow benches use 28" [-27.7= -1.0 psi negative] of differential pressure [what some call incorrectly vacuum].
They are testing at 13.7 psi pressure against the 14.7 in the air..........a 6.8% total loss in density for every component from the cylinder outwards.

Since meter accuracy is 2% you pick the appropiate unit from the 3 on hand................with inexpensive units you can get accuraties of 0.0025 psi. against an atmospheric 14.7 psi.

This is definitely something aftermarket manufactuers NEVER want you to know.........

 

Thanks for the test data DaveO,

This is real. It's the stuff I like to see.

It is hard to make a 1:1 comparison because of the different ambient temps but the testing is all in the right direction. I won't criticize your efforts at all. Controlling all the variables is not easy to do, takes a lot of time and can be costly.

Thanks! Keep up the good work!
Tony

PS. Today I will measure pressure drop across the Stillen sedan catback muffler Vs straight pipes.

2004 G35 6MT Blk/Blk Sedan Stillen Air, Stillen Exhaust

 

so which intake is best?

 

Its just my opinion but I say Stillen is better by a long shot. What sets it apart is the heat shroud that so thoroughly separates it from the hot air in the engine compartment.

The Pop charger is still a good unit but it will unavoidably suck in some hot air.

...Now if you can do what DaveO did by putting the Pop Charger filter inside the Stillen air box you would be doing even better!