From Bruce Shinkle, coach #660,

>How is your H2 air box working?

I am very happy with it. It appears to be doing the job and is not showing any evidence of air restriction.

> Did you mount it right side up, or upside down?

I mounted it to the ceiling of the left side of the engine compartment using the three integrated mounting legs that originally were used to attach it to the left side of the firewall of the H2 Hummer. This means that I rotated it ninety degrees from its original orientation. The air is drawn in from the left through the large oval opening, passes linearly through the filter and exits in a straight line to the right to the engine. The connection tube is about 3 feet long.

>How did you join the input side of the box to the airscoop on the side of your coach?

I didn’t! I positioned the intake side of the filter housing about a foot inboard from the grill on the left side. I had previously removed the after market exterior air scoops that came on the coach as I felt they were not needed and detracted from the looks of the coach.

>Do you have any type of particle separator built in for rain?

No. Because I positioned the filter canister inboard and up from the side grill it is not exposed to rain or road moisture. Being away from the engine, it gets cool air and being attached to the top of the compartment keeps it out of direct air flows and the accompanying air born particles. It gets cool (confirmed by intake air temperature), clean, dry air. Additionally the filter material is the new Donldson microfiber which is a polyester (see files section of FMCMotorCoach2) and not paper so it is not affected by reasonable amounts of water. It won’t collapse as paper will if it gets wet.

>Is the output side a 4 inch opening?

Yes.

> You mentioned you might put two in parallel - why? One seems like it would do the job very well.

I was initially a little concerned about the airflow capacity since the Hummer engine is smaller than the 440-I. However, after allowing for the 6,000 rpm red line of the hummer vs. my personal redline of 4,000 rpm that concern disappeared and I have only used one. The capacity concern also disappeared after actual use. My Edelbrock MPI system has a continuous vacuum readout that has confirmed that there is no intake restriction under high rpm and open throttle.



Bruce, in case you missed it, here is a link to the files at FMCMotorCoach2 that describe the new filter material and honey comb structure.

http://autos.groups.yahoo.com/group/FMCMotorCoach2/files/Donaldson%20PowerCore

Note that the PowerCore filter media is not available on the after market. It is currently restricted to OEM’s only. I was fortunate enough to be able to find that the Hummer H2 canister and filter is a perfect fit for our coaches in my opinion – the latest in filter technology with off the shelf components. It also makes for a very simple, clean installation that helps to unclutter the engine compartment. Visit the shop of your local Hummer dealer and see if they have any excess canisters and filters removed to upgrade the actual Hummer H2 to a more off road exterior system. That’s how I got mine.