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Old 03-16-2005, 01:35 AM
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whats THIS

look what i found in one of my old magazines i thaught it was real bad to do this. Read the screen play part.......
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Old 03-16-2005, 01:38 AM
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here is a better pic
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Old 03-16-2005, 01:39 AM
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need better pic
Old 03-16-2005, 01:41 AM
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posted just barley 2


late that would be stupid lets ruin our engine
Old 03-16-2005, 01:43 AM
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how much air do we flow with them in.
Old 03-17-2005, 12:51 AM
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Originally posted by jojo22
that would be stupid lets ruin our engine
Removing screens has been done since the beginning of time, and I've yet to hear anyone say anything bad about it. The fact is that if by some great act something actually got past your air filters, it would be tiny enough to fly right past those gaping holes in the screens. They're completely pointless, and only for guys that poke holes in their filters before driving through confetti. Stock cfm according to TPIS: 434. No screens: 512
Old 03-17-2005, 06:47 AM
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The point of the screen is not to keep stuff out of the motor, but to smooth and straighten the airflow through the MAF. This helps ensure that the air at least in part passes over the filaments. Some of the LS1 guys have done the descreening thing and really regretted how the car ran afterward. I left the screens (flow straighteners) on my LS1 MAF. At ~3.5 in diameter, I doubt the car would ahve ever run right at low load without the flow straightener.

if you want more flow, build a freq. to voltage converter and use an LS1 maf rather then that old bosch stuff. On top of that, used LS1 mafs are dirt cheap.
Old 03-18-2005, 12:44 AM
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If the point is to straighten out the air for the filaments, what's the purpose of the screen after the filaments?
Old 03-18-2005, 12:50 AM
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Originally posted by dimented24x7
The point of the screen is not to keep stuff out of the motor, but to smooth and straighten the airflow through the MAF. This helps ensure that the air at least in part passes over the filaments. Some of the LS1 guys have done the descreening thing and really regretted how the car ran afterward. I left the screens (flow straighteners) on my LS1 MAF. At ~3.5 in diameter, I doubt the car would ahve ever run right at low load without the flow straightener.

if you want more flow, build a freq. to voltage converter and use an LS1 maf rather then that old bosch stuff. On top of that, used LS1 mafs are dirt cheap.
Dead on answer. I still have the screens on both sides of the 87 TPI MAF. When most of the LS1 guys were taking the screen off their MAF"s and porting them, I just bought an aftermarket housing and put it around the electronics. Now everybody wants to borrow my MAF ends to tune their cars or buy them. No way. My car is running ok with the aftermarket ends but I will likely put back the stock housing. Screens are there for more of a reason than keeping out dirt.
Old 03-18-2005, 12:53 AM
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Originally posted by 88Z
If the point is to straighten out the air for the filaments, what's the purpose of the screen after the filaments?
To keep curious oily fingers off sensitive electronic parts that could be damaged by the mere presense of finger oil.
Old 03-18-2005, 06:27 AM
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Originally posted by 88Z
If the point is to straighten out the air for the filaments, what's the purpose of the screen after the filaments?
To disturb any reversion/backfire wave and hopefully keep it from killing the hot wire.
Old 03-18-2005, 09:34 AM
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This is a pretty good write-up on the topic:

http://www.gmtips.com/3rd-degree/dox...maf-screen.htm
Old 03-18-2005, 12:15 PM
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Originally posted by Red Devil
To disturb any reversion/backfire wave and hopefully keep it from killing the hot wire.
The newer mafs dont have it, but look to be reasonably durable inside. Ive backfired through mine and it seemed to take it without any ill effects. Just a WAG, but maybe the rear screen could also be to prevent post-wire turbulence at the rear of the MAF that could cause effects upstream.

Personally, Id be more worried about the imposed 255 gram/sec airflow limit in the ecm rather then the airflow potential of the stock MAF. Doesnt matter much if the computer doesnt add fuel to all that extra airflow. With a small ammount of reasearch and tweaking to the stock calibration, a larger, higher flowing MAF that wont peg on decent motors could be used.
Old 03-22-2005, 09:31 AM
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I took mine off 2 years ago, and never noticed a difference, good or bad!
Old 03-22-2005, 09:48 AM
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Its BS...the thirdgen screens dont straighten the airflow. They were designed to protect the delecate hot wire. In order to remove any airflow turbulance you would need fins inside the MAF. Remove the screens..they are a restriction...... Hey I got an idea lets all put the Tornado in our intake tubing.....if the screens straighten the airflow in the MAF so well imagine the HP gains of the Tornado.....Remove the screens..they are a restriction built into the MAF by the designers because they knew how delicate the hot wire MAF design was.
Old 03-22-2005, 11:12 AM
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TPIS has an actual dyno sheet from where they removed the screens and fins from a MAF on motor with a cam. There is an increase in HP over all RPM ranges, with some gains as high as 10 HP.
Old 03-22-2005, 11:28 AM
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I took mine off in my LT1, it was WAYYYYY more restricting than the TPI ones (i only had 1 screen btw) and I noticed that at WOT on the top end it breathed better.
Old 03-22-2005, 11:28 AM
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I took mine off in my LT1, it was WAYYYYY more restricting than the TPI ones (i only had 1 screen btw) and I noticed that at WOT on the top end it breathed better.
Old 03-22-2005, 11:52 AM
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On a karman MAF you need the screens. On a hotwire MAF they serve no real purpose.




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