New Filters and MAF Comparo

[4everRS]

Well, I got new air filters. They were about due, and while doing some shopping on Amazon, I decided to get a couple K & N filters. I have been told before "don't waste your money" "just buy the paper ones". And for whatever reason, I ignored it.

So I wanted to check and see in the logs what the difference would be. I was a little surprised. Below is a chart of MAF and RPM, identical runs, engine warmed up, ect ect.




I think this is enough evidence of why NOT to waste your money on the K&N's. I was really expecting to see a little improvement in MAF. But no.

[4everRS]

I am also not real happy that I'm not going over 400 on the MAF's. My mBar of boost isn't great either. I don't get to 2k. Barely gets to 1900. Requested and actual.

[ben916]

Stock setting on the APR?

How old are your MAF's?

[ttboost]

Hate to say I told you so, but....

I spent a good afternoon on a dyno with my 996 Turbo testing this theory. Was tired of all the speculation about air filters, so I figured I would test them myself, back to back, same day, same weather, same dyno and actually waited and tested with the same engine and coolant temp. From paper, to K&N to no filter, power never varied more than 10-12hp. The problem was that those power difference were different everywhere in the rev range. Too inconsistant for me to justify running a filter that just doesn't filter that well. NOTHING filters better than paper. If you don't keep that K&N clean and oiled every week, you are just sandblasting your cylinder walls, period.

[ttboost]

I thought my MAF's were bad regarding my latest issues. Turns out MAF values are directly related to boost (I know, thanks Capt obvious). I was in limp mode (.3bar) and was only seeing 140g-150g, per MAF, at WOT during this time. Ultimately in the end, I think it was leaking MAF seals that was my problem. I have disconnected my MAF's from my airbox and fitted them directly in my plenum. They are NOT connected to my airbox any more. They will not come out unless I TAKE them out. My thought is, worst case scenario, I get a smidge of unfiltered air, but never have this problem again.I was actually able to push the airbox down far enough, so I think the rubber O rings in the airbox actually seal on the top of the MAF's, so not really even worried about the unfiltered air thing. My car now makes 1bar easily and I am now seeing 200-215g per MAF...

PS...drove my car ALL day yesterday...almost 300 miles and not so much as a hiccup...