Air Filter Housing Restriction

[Padawan]

Originally Posted by Jaxonalden

I know of no other company that has a screen to catch the big chunks. I'm cutting out this screen and replacing the one in my car.

Most of them do. In fact, every car I've worked on that had a MAF (as opposed to a MAP) had a screen like the one here.

Not only does it serve to keep out "large chunks", but it more importantly influences airflow over the sensor.

You can read more here: http://www.gmtips.com/3rd-degree/dox/tips/maf/maf-screen.htm

[coreseller]

Originally Posted by Padawan

Most of them do. In fact, every car I've worked on that had a MAF (as opposed to a MAP) had a screen like the one here.

Not only does it serve to keep out "large chunks", but it more importantly influences airflow over the sensor.

You can read more here: http://www.gmtips.com/3rd-degree/dox/tips/maf/maf-screen.htm

Ditto that. I've put in a couple of CAI (Cold Air Induction) kits in other cars, I haven't encountered one without the screen, domestic or import. Oh and BTW, there was always a seat of the pants difference felt with them, one verified a 13 HP increase on the dyno, these completely replaced the stock airboxes though.

[Jaxonalden]

OK, I'll post this to anyone out there that has an EVO intake installed. Does that intake have a screen just before the OEM Mass Airflow Sensor? I went to the site that sells them and could not see or read that it does. It does utilize the stock sensor so, if you guys are right, will have this screen installed. I checked my SUV, my wife's car and my Harley and none of then have a screen in front of the MAS. Everything else I own has a carburetor.

I can see where you think it should. In high RPM engines, the air flowing past the MAS will act like a wing on a high performance aircraft and will create a boundary layer of air giving false readings. The screen will act as vortex generator breaking up that boundary layer. On an aircraft wing it allows the flight controls to be more effective at high air speeds.

So with that said I need someone that knows first hand what the EVO intake has inside that pipe. Pictures would be nice also. Until then I'm swapping out for my screen-less stack (which only took an Exacto knife to cut out). If I get a CEL, I will post it and won't hide the fact that I was wrong in my assumption.

I should just go ahead an get the EVO because the air in a stock air box takes no less than 4-90 degree turns in less than 12 inches!

[Quickurt]

Originally Posted by Jaxonalden

OK, I'll post this to anyone out there that has an EVO intake installed. Does that intake have a screen just before the OEM Mass Airflow Sensor? I went to the site that sells them and could not see or read that it does. It does utilize the stock sensor so, if you guys are right, will have this screen installed. I checked my SUV, my wife's car and my Harley and none of then have a screen in front of the MAS. Everything else I own has a carburetor.

I can see where you think it should. In high RPM engines, the air flowing past the MAS will act like a wing on a high performance aircraft and will create a boundary layer of air giving false readings. The screen will act as vortex generator breaking up that boundary layer. On an aircraft wing it allows the flight controls to be more effective at high air speeds.

So with that said I need someone that knows first hand what the EVO intake has inside that pipe. Pictures would be nice also. Until then I'm swapping out for my screen-less stack (which only took an Exacto knife to cut out). If I get a CEL, I will post it and won't hide the fact that I was wrong in my assumption.

I should just go ahead an get the EVO because the air in a stock air box takes no less than 4-90 degree turns in less than 12 inches!

You may not get a Change Engine Light, but it may run like crap or stumble at certain RPM ranges, etc.
I put a K&N ram tube, ot whatever they called it, on an RX8 and it used the original MAS and had no screen in it, but neither did the OEM airbox.
Made the car so loud on intake noise, I couldn't stand it.
Know anyone who wants one?

[Jaxonalden]

Swap out and 50 mile test drive complete. No CEL and I can swear that the intake noise is throatier, maybe the screen suppresses some noise. Driving the car through the twisty's does seem to run similar to a sexual molested primate. IMHO

[Jaxonalden]

While sitting around this weekend I decided to do a little research on a couple of issues;

1. Over servicing of K&N air filters. That myth is settled here;
http://www.knfilters.com/MAF/massairfindings.htm

2. Removal of the intake screen (reason for the thread). I've visited sites, read posts and learned about the different mass air flow sensors. We utilize the hot wire type. The wire is maintained at a constant temp and the air flow moving across it will cause it to loose heat faster. The ECU will compensate by sending more current and measures this current flow and puts out a voltage signal. This wire is made of platinum (hence the $250+ replacement cost) and is susceptible to damage if a foreign object should come in contact with it, (the screen). So are the internals of our engines, so if this happens I think the MAF is the last thing I would worry about.

The wire is self cleaning, (from what I read) at engine shut down this wire is heated to 1800 degrees to clean itself, unlike a dog that can lick his balls. A couple GM forums had CFM numbers with and W/O the screens but the 180CFM difference was based on their size and density of screen. I know ours is restrictive and the filter I use will keep out anything harmful. As I've said, I will continue to run without. If a CEL occurs and its determined to from the MAF I'll post the results.

[Franco]

Hi, Thanks and keep us posted and I like your