cmillard

Ask Mike Licht who designed the MAF translator, he mentioned they barely say a 1hp gain going with a larger MAF on a 500 Hp car - I'd say that certainly wouldn't signify a restriction on the 300-400 hp and below crowd.

Taking the screen out will affect low rpm air meter quality, but hey it's your car you can so what you want. try a blind test and see if you can tell a difference.. never will.

Dan K

HAHAHA!!! Good catch. I should have added that I have seen people take their air filters out at the track and that the screens are just added protection. Maybe keep a leaf out or something.

Dan K

I agree completely. Good point about the screens straightening out the airflow. I forgot that one.
Like I said, the only reason I can see to touch a MAF sensor would be to replace it with one that can flow more air.
But as you mentioned, is a 300-400hp car going to see a restriction...probably not.
To each his own, I guess.

You know, I'd like to get a ported and descreened MAF to put on my car and do a little datalogging. I'd like to see what the MAF is seeing and what effect it has on the blm's. Wonder what else I could find?

Tech

I've got de-screened ends I'll trade ya for ones with the screen in it.

Dan K

No, I don't want to get rid of my stock one.
But I would like to find one that has been ported/descreened.
Or maybe I'll just buy a cheap unmolested one and molest the snot out of it and see what happens.

FireAm94

Huh? I think you totally misunderstood what he said. That had nothing to do with cleaning the MAF element.

Joe:

fordkiller94

OK HERE ARE THE LATEST STATS:
21 VOTES TO DESCREEN THE MAF...
23 VOTES TO LEAVE IT ALONE AND KEEP THE SCREEN..
SEEMS LIKE THIS SCREEN MOD IS STARTING TO LOSE ITS POPULARITY.. SO FAR I THINK I'LL GO WITH THE "KEEP THE SCREEN CROWD"..BUT COULD CHANGE MY MIND...DEPENDS ON THE VOTES.

Brent94Z

Nope, that's not what the data shows. It shows a snapshot of airflow at a certain differential pressure across the MAF.

I like to use the analogy of a stock air box on a 550hp killer 396 stroker motor. Example: You've got this killer 396 stroker which dynos at 550hp with the stock airbox installed. However, it might dyno 600hp with a K&N FIPK. So, for those who say you only benefit from removing the screen if your engine requires the max air flow (over 759 cfm in this example) should also be saying that changing your air box on a stock LT1 will do no good because it has been proven to be good to at least 550 hp. Follow me? We all know that changing the stock air box to a K&N FIPK even on a stock LT1 is a very good mod and gives typically between 10 and 20 hp. This is true even though the stock air box "worked" on a 550hp stroker. However, even though it worked doesn't mean it "worked best"

While removing the screen on a MAF is not nearly as beneficial as the air box example I gave above, similar principles apply. It has been talked already that it is believed that removing the screen may only give you ~1 hp. Well, that's a horse power and if it's free, it's for me. This is probably fairly accurate because I've done some crude testing with and without the screen with scan tools. I could see no noticable change in grams per second air flow with or without the screen. However, when doing the same crude testing with a K&N FIPK, I found that my stock Trans Am went from ~230 gps air flow at redline with the stock air box to ~260 gps air flow at red with a K&N FIPK. That's why you get a 10 to 20 hp gain with the K&N FIPK but maybe only a 1 hp gain with a descreened MAF.

I'll also add that some have mentioned the screen being there to provide for a better air flow across the sensor for a more accurate reading. While I believe this to be why the screen is there, I have to question how much it really helps the sensor give a more accurate reading, because, with my crude testing I saw no difference in sensor "behavior" with the screen installed as compared to it being removed. The gps readings for me were the same at idle all the way to redline with no difference in fluctuation or anything. So, for me, it didn't seem to affect the sensor in anyway at all, didn't affect my gas mileage, didn't afffect my idle quality, and basically didn't do anything negative what so ever. It might have given me 0.001hp, 1hp or maybe more? Don't know, don't care... so long as it doesn't hurt me. Since it didn't hurt me, I'll leave it out. If I find I have problems like some others have had, I'll stick it back in.

I'd also point out about this screen thing that the I'm unaware of any aftermarket sensor which comes with a screen. Are there any? I have an aftermarket sensor (not a Granatelli) and it doesn't have a screen or provisions to even put one in. I also have a Granatelli and it has no screen. If the screen really was a big deal and really was needed, don't you think the heavy duty testing done by the Engineers of these companies would have shown it was needed? If needed they would have included one in their aftermarket sensors... they don't. This is similar to my AS&M 58mm throttle body. I'm sure AS&M did some serious testing with this throttle body. I'm not sure if many know or not but the AS&M 58mm throttle body doesn't have the coolant line hook-ups... you are forced to do the throttle body coolant bypass mod when installing this throttle body! Also, this throttle body didn't come with any warnings saying it could only be used in climates where it didn't snow Therefore, I'll assume the AS&M engineers found the coolant channels in the stock throttle body unnecessary. I don't want to say this is exactly the same as the descreened MAF but just an example of where sometimes GM might be a little over conservative. I know of not a single person who has had issues with the throttle body coolant bypass mod yet there are several who have reported idle problems when removing the MAF screen while others like myself don't have any problems. Why the majority don't have problems but some do is something I can't explain and is probably why topics like this always get so much attention with people on both sides of the fence... unlike the !TB mod where I can't think of anybody who says that it is a "bad mod"

Dan K

Maybe you need to read what I said again...AND what I was replying to, because I don't understand what you just said at all.

Dan K

Great. That keeps me from having to do this little experiment.
Did you do any datalogging with ported ends or anything?

Not that I've ever seen or heard of.

I think most of the problems that people have are with ported ends and actually porting their maf sensor...not necessarily removing the screens.
I think that's also where most think they're getting more power out of the maf mods.

You say if it doesn't hurt do it, I say if it doesn't help don't do it.

IslandZ

Here's the biggest reason for keeping it.
I noticed my car running roughly some time ago, and I started to check what it was. Well when I removed the tube to the MAF I saw some black foam filter thingy on the maf screen restricting airflow. I have a Moroso filter and the ONLY place this foam could've come from is the air pump. Imagine what would've happened if this crap would've melted on the electronics of the MAF, or entered a cylinder. Glad I had my MAF Screen on.
I have since put a filter in the line that goes from the air pump to the air filter tube.
So I vote NO to removing it.
1 hp isn't worth a risk (however remote it is)

shoebox

I don't see how saying "aftermarket MAFs don't come with screens" proves anything about the need for the screen. GM and everyone else designed their own MAF and I would say GM designed theirs to work with a screen and the others did not. When GM changed the design of the MAF later, they removed the screen. Was it because they discovered that they made a mistake in putting it in the early ones or because the new design negates the need for a screen? Unless you were on the design team, how are you going to know?

Take it out if you want, but don't destroy it doing so. Then if you have problems (some ppl do) or change your mind, you can put it back. It is that simple.

Perry93TransAm

2CNTRY The airpump couldnt have put that debris there because the hose attached to the filer housing is sucking into the airpump as well. Unless the airpump was reversed wired and blowing into the MAF instead of sucking from that area. This was a big thing on the thirdgens too (which I have owned seaeral) and I allways removed the screens on it and had no problems. To each his own I guess (I like Shania lol).

fordkiller94

anymore votes on this?

Mir Hussain

Fw things nobody mentioned.
WHen you have descreen/ported Screen. Your computer not getting right Date. It think you getting more air. Why because MAF tables where programed with Channel and with screen. Now those are removed so there is more air comming in; but mostly its turblance air. Well what your PCM do. Dump more fuel. your 02 says :wtf: You A hole PCM, cut back the fue.l PCM go Huh tries to use different Fuel cell and keep playing with Fuel LT trims. In result you get Lower MPG, Rich Mix, little Less power, Dirty tips, and upset PCM