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Discussion Starter #1
I've been reading about the S/C GTO's needing their MAF sensor de-screened to get all their power. Would this apply to a NA car? From what everyone is saying, our MAF is good to 350 rwhp, so at my 388 would the biggest gains be made by removing the screen and how hard would it be to tune it that way?

:confused:
 

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I like boobs.
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I believe the screen is there to help the MAF get a proper flow reading under "normal" conditions. The catch is, the screen is no doubt a restriction. Remove it and it could hurt the fuel ratio, leave it and it no doubt hurts intake performance. I'm sure its worth trying a "before and after" on the dyno to see how much it frees up.
 

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I asked the same question a couple days ago. The consensus seems to be that removing the MAF on an NA car would lean the car too much.
 

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Go Tigers!
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jagular said:
I asked the same question a couple days ago. The consensus seems to be that removing the MAF on an NA car would lean the car too much.
Since his car is not stock anymore, a good tune should take care of any
problems of removing the screen. With it removed the tune will adjust
to the proper ratios etc. I would think.
 

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what confuses me is people saying things like particles making it past the intake and hence would be stopped by the screen and now its basically a given to have it removed for Maggie so should I be worried or what? Would it be better for Maggie to just buy another MAF like the one posted in a diff thread(mistermike) or just get the stock maf descreened?
 

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Discussion Starter #6
I don't know how a screen with 1/8" openings is going to stop anything that a filter with much smaller openings didn't stop so I don't think it is there for protection.
 

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cjlannoy said:
I don't know how a screen with 1/8" openings is going to stop anything that a filter with much smaller openings didn't stop so I don't think it is there for protection.
Exactly. Removing the screen does NOT put your engine in anymore danger.
Now if your filter or tube come loose then there could be a problem with larger
debris getting in, but that I would think would be a very rare occasion.
 

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Descreening will alow alot more air in but if your tune is not set up for it or your bolt ons do not require it than it's not a big deal. Alot of fbody guys have done it and alot have given up on it. Messing with MAF makes a good dyno tune damn near impossible.
 

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Discussion Starter #9
I think something is going on with my car and I have to either "uncork" the intake or exhaust and I'll see some major gains. After reading that our MAF is only good to 350 rwhp I would think that would be the solution. If I take the screen out is it that much more difficult to have it dyno tuned? I figure if they can do it on the S/C cars and they go from somewhere like 360 rwhp to over 400, I should see about the same.
 

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cjlannoy said:
If I take the screen out is it that much more difficult to have it dyno tuned? I figure if they can do it on the S/C cars and they go from somewhere like 360 rwhp to over 400, I should see about the same.
If you get your car professionally tuned I see no problem in getting that dialed in. They'll hook up a program(hp tuners, ls1edit), get some feedback
change some settings, do some more testing and I see know reason why they
cannot get it dialed in. The key is getting it done by someone who knows what the hell is going on.
 

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the problem is that your descreened maf will give you a "slight" increease until your pcm relearns and then "most" if not all your gains will disappear. it simply isnt worth the effortand makes you car harder to tune with edit, the screen isnt the restiction in the intake, my car makes 400fwhp with a screen.
 

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You could hack out the MAF screen, the screen is there to direct the flow of air without the screen some un metered air can pass and the engine runs slightly leaner (more power). Of course the block learn will figure things out, and try to get fuel trims back to 0.

You could get a Z06 MAF that is factory designed descreened or a SLP MAF that was tested in GMHTP this month and showed 2hp increase on a bolt on '02 Fbody. OR you could just eliminate the MAF all together, some tuners in australia are having success with MAFless tuning. You can get a MAFless tune PCM from CAPA. Instead of using the MAF the MAP sensor is used as primary engine load input(speed density I think its called.) You also have to replace the intake pipe. Holden used a MAFless tune on the HSV GTS. The MAF is a restriction too.
 

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Maffless is definetly the way to go, improved drivability far more grunt down low and increased rwhp up to 30+ over a good maf tune. next thing on my hit list I'm hoping to climb from 230 to 240+ rwkw
 

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OK, lets get some things straight;

1) The screen is there to straighten airflow for a STOCK airbox in order to get an accurate measure across the thermistors in the MAF. The stock airbox creates turbulence and other air circulation to quell intake noise. How many times do you see cars (like the F-Body's "mickey mouse ears") with additional plastic boxes and such. This is to quell intake noise. The byproduct is turbulence in the airflow.

2) For those of us who have CAI's, We have elimintated these air baffling and other noise quelling instruments. CAI units suck air straight in and then send it straight into the the MAF. There is NO TURBULENCE, hence the screen ISN'T needed now!

3) Removing the screen will do 3 things. 1) increase throttle response due to 2) the ability of the air to react across the thermistors and 3) The increase in volume.

Your MAF measures air in two ways. 1) Hertz (hz). This mesures the air speed. The higher the hz frequency, the higher the air speed. 2) Volume. It measures this in pounds/hour. Naturally, the higher the pounds/hour, the more volume is being inhaled.

So in essence, removing the screen A) increases the speed with which the air crosses those thermistors and naturally can measure greater amounts of air.

Any leaness is temporary as the O2's will catch it and will then be corrected.
 

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CMNTMXR57 said:
Your MAF measures air in two ways. 1) Hertz (hz). This mesures the air speed. The higher the hz frequency, the higher the air speed. 2) Volume. It measures this in pounds/hour. Naturally, the higher the pounds/hour, the more volume is being inhaled.
Close, but the "Hz" does not indicate speed. The GM MAF measures air mass per time (which implies volume) directly and outputs a square wave signal that increases in frequency (Hz) as the mass of air increases. So higher Hertz means higher air mass flow.

The measurement is based on a heated hot wire and a reference cold wire. The hot wire is cooled by the air flow, the cooling changes it's resitance. Comparing the hot and cold wire restance tells you the air mass flowing by the hot wire, i.e. how much air is cooling the wire.

If there is turbulance in the air stream, the hot wire will have "hot and cold" spots and will not measure correctly. Hence the need to quell turbulance.

The point is, you want to have a straight shot across the MAF wires, bends and turning corners just in front of the MAF is not good.
 

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MAFless hmmmmmm, I thought that everyone was moving away from speed density to allow for better and more precise tuning. :confused:
 

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I took the screen out the first week I had the car and never noticed any difference good or bad. I dont think you gain anything, unless it is slight. It has been dynotuned three times since then and it didn't affect the tune as far as I know.
 

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Robert Duncan said:
Close, but the "Hz" does not indicate speed. The GM MAF measures air mass per time (which implies volume) directly and outputs a square wave signal that increases in frequency (Hz) as the mass of air increases. So higher Hertz means higher air mass flow.

The measurement is based on a heated hot wire and a reference cold wire. The hot wire is cooled by the air flow, the cooling changes it's resitance. Comparing the hot and cold wire restance tells you the air mass flowing by the hot wire, i.e. how much air is cooling the wire.

If there is turbulance in the air stream, the hot wire will have "hot and cold" spots and will not measure correctly. Hence the need to quell turbulance.

The point is, you want to have a straight shot across the MAF wires, bends and turning corners just in front of the MAF is not good.
Pounds per hour measure the incoming air mass. Frequency measures speed. The higher the frequency, the higher the air speed. Unless physics have changed!

Blow across the top of a bottle, you know you get a certain "Frequency" to the tone. Now blow faster, doesn't that tone change, generally to a higher pitch, errr, FREQUENCY!!!
 

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Shag Finger said:
MAFless hmmmmmm, I thought that everyone was moving away from speed density to allow for better and more precise tuning. :confused:
Manufactures yes, speed density was really OBD I kinda stuff and Ford EECIV. But it has been on toyota 5S-FE 4cylinders for years. Its whatever goes around comes around.
 
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