Lozz is right. The MAF screen is designed to produce laminar (straight flowing) air flow to the MAF sensor. Without it, the air that flows in will be turbulent (swirling) air that will not give a consistent reading to the sensor. It is best to keep it in.

The other mod (removing plastic in front of air intake duct) is definately beneficial. I have noticed good gains in both my Proteges after this mod. The acceleration was smoother in both cars and the RPM's dropped faster in the auto. I also built a bug deflector out of speaker grill covers to keep larger bugs from entering the air box. You will still need to clean your air box out more often than before, but the engine definately runs better. Here's a few pics of my grill. They have about 1/8 " holes in them. I ran the car with them on and off and didn't notice any difference, so I'm keeping them on to keep the buggies out.

 

I didn't even think about that >_> and I live almost in bug country USA.. xD
o well, the ebay SRI is on order so It can handle a few hawk mosquitoes for a little while longer..
I'm going to go get some epoxy and see if I can't put my screen back in..

 

And then what?

 

well i dont know about the air spinning or what not but ive had my "waffle" out for over a year or sonow and havent had any issues with it being removed. gas mileage is the same....not cels thrown. but to each his own.



james

 

I acutaly noticed a small mileage decrease when I removed mine, it could be just my imagination though, but it droped from about 300 to roughly 260-280, that was after it was removed and I reset the ECU. After I put it back in and reset the ECU again it went back up to about 300-310miles/full tank. 280 is probaly within the margin of just milage loss due to agressive acceleration or in stop&go traffic alot though.

 

Come to think of it, I have noticed a small decrease in mileage. But I was also attributing it to aggressive driving. I think I'll re-install before I fill my tank and check my mileage again.