In the SSOA FAQ it says that the screens create less turbulent air flow and should not be removed unless you are doing a mod on the heads, cam, etc... This does not make sense to me. It seems to me that the screens would be blocking airflow. And anytime you put an obstruction in the way of air the air will become more turbulent.
I have never heard anyone say that they would not do this mod or that it would adversly effect performance. In fact I've seen the opposite... Claims that there is improved midrange (makes sense, more flow more top end and midrange power) and better throttle response.
HELP!!!
I still have my screen in my MAF.
Look at it this way, your faucet has a screen on it to keep the water flow straight and nice (lack of better terms mind you.) remove that little screen and the water goes everywhere. Its not just a nice smooth flow anymore.
But, seeing as I am not a professional, this is only my opinion. My broh Chab has his screen removed (I think) and it has a slight irratic idle. (its slowly going away after the PCM program)
Doug
Good analogy with the faucet though. But I bet if you measured and timed the water coming out of the faucet you would find you get more cfm as well.
And with all the other things the air has to pass through after the MAF it would seem to me that the turbulence would be a very very minor factor.
[ 22 March 2001: Message edited by: Kuma ]
We pulled the screen on my friends 97 WS6 and he has had no problems. It's always a good idea after any mod to pull the battery and have the ECM re-learn things.
quote:
Originally posted by AndrewB:
There are two reasons why it's there. One is to straightened the air flow (this is documented in GM in documents). Two, as a last ditch barrier to prevent large crap from visiting your engine (GM knows they build shit airboxes, so a little more security wont hurt).We pulled the screen on my friends 97 WS6 and he has had no problems. It's always a good idea after any mod to pull the battery and have the ECM re-learn things.
Thanks, that sounds reasonable. I'm going to be installing the SLP !CAI (if SLPonline is back up for me to order it, heheh) and at the same time I'm going to try the screen mod. I'll let you all know how it turns out. I'll take your advise and disconnect the battery as well.
At the same time I'm planning on doing multiple mods. But I'm thinking about doing them one at a time so I can see what each does. That way if one of the mods causes trouble I can narrow it down as to what caused it.
Removing the MAF Screen provides an additional 170-180 CFM of flow (the stock MAF flows in thousands). It also allows 'rougher' air to hit the sensor. That 'rough' air causes the sensor to send irradic data to the computer which must then try to figure out what the correct flow should be, so it can adjust the fuel to air ratio. usually the computer fails to get the right mixture and makes it to rich in fuel. which is why people see decreased fuel mialage.
One thing I've never seen is anybody actually prove with dyno runs, and track runs that thers any performance gain after 200 miles. The ony thing I've seen is people talking about SOTP feeling which makes me beleive that the SOTP performance thier feeling is mental.
quote:
Originally posted by John -- '01 HAWK:
the MAF screen provides laminear (sp?) flow to the sensor. Essentially it straightens out the air flow hitting the sensor. which allows the sensor to report an even reading to the computer.Removing the MAF Screen provides an additional 170-180 CFM of flow (the stock MAF flows in thousands). It also allows 'rougher' air to hit the sensor. That 'rough' air causes the sensor to send irradic data to the computer which must then try to figure out what the correct flow should be, so it can adjust the fuel to air ratio. usually the computer fails to get the right mixture and makes it to rich in fuel. which is why people see decreased fuel mialage.
One thing I've never seen is anybody actually prove with dyno runs, and track runs that thers any performance gain after 200 miles. The ony thing I've seen is people talking about SOTP feeling which makes me beleive that the SOTP performance thier feeling is mental.
There must be something to removing the screen. Have you noticed that ALL the so called HiPro after market MAF's have no screens?
I will say that the combination of the Whisper lid and the MAF ends did seem to open up the top end of the engine a little. After I put on my exhaust, it seemed to get even better.
Just my .02.
quote:
Originally posted by Kuma:
There must be something to removing the screen. Have you noticed that ALL the so called HiPro after market MAF's have no screens?
I forgot to add that I'm talking about the ls1. The lt1 behaves just a little bit differnt to the MAF scrren removal
They also include sensors that have been recalibrated. GMS MAF is an excellent example, they've removed the Screen and then they calibrate every unit. Even then the MAF has problems on most the cars its installed on it either makes the car run to lean on some occasions to rich. So you can send it back to GMS and they'll recalibrate it again.
The MAF ends keep the stock sensor, some even have same I.D as the stock. Fot the ones that keep the same ID, I haven't seen any proof of performance.
BTW the SLP 85mm MAF has a screen.
quote:
Originally posted by John -- '01 HAWK:
I forgot to add that I'm talking about the ls1. The lt1 behaves just a little bit differnt to the MAF scrren removalThey also include sensors that have been recalibrated. GMS MAF is an excellent example, they've removed the Screen and then they calibrate every unit. Even then the MAF has problems on most the cars its installed on it either makes the car run to lean on some occasions to rich. So you can send it back to GMS and they'll recalibrate it again.
The MAF ends keep the stock sensor, some even have same I.D as the stock. Fot the ones that keep the same ID, I haven't seen any proof of performance.
BTW the SLP 85mm MAF has a screen.
Hmm, just checked out GMS. Their dyno charts show as much as 18 hp increase on the LT1 engine. It does seem to make a greater increase on the LT1 vs LS1. Hmm. Maybe I'll leave out something like the underdrive pullies on my april 1st order and get the GMS MAF. Also they guarentee the product. Thanks for the info dude.
The stock MAF flows enough for the engine to operate normally, the really congestion is exhaust. I would look at that route before I did the MAF
Also I would go with maf ends if you aren't going to headers, or head work. Ask KenC about his MAF ends.
quote:
Originally posted by John -- '01 HAWK:
That report is BS. The car got that much in gains because it had other work (Headers, etc) done to it they forgot to mention. Similiar to what what happened on the SLP long tube headers.The stock MAF flows enough for the engine to operate normally, the really congestion is exhaust. I would look at that route before I did the MAF
Also I would go with maf ends if you aren't going to headers, or head work. Ask KenC about his MAF ends.
The report I saw was on their web page and at the top it says that it's a stock 1996 Z28. If that is untrue then not only did the forget to mention that the car was moded the stock numbers don't show any HP mods. If the are being deceptive about it I think there would be a strong case for false advertising.
Thus for the mods they had they got that 20hp when the maf was installed. It's not deceptive because it's what the magazine printed. none of the data is GMS's its all the mags. very easy to pass the buck
Now I'm not saying it's a bad mod I'm just saying the price to the actual performance given is very high. People do see perfomance gains (5-10hp) but they also see the car run lean. theres cheaper products for the same performance gains.
