screen delete on MAF
11-23-2005, 05:18 PM
#41
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I don't know if anyone will read this after all the other posts... but here it is anyway...
This is a bit of real world results from a descreened MAF on my H2 with Radix and Cam-
I did not dyno before and after. I did not feel any SOTP gains (granted a couple of horsepower is not detectable with 6800 lbs attached to it). But I did see my Long Term Fuel Trims go about 5% leaner across a couple sections of the RPM range. The other sections went 2 or 3% leaner. It wasn't quite linear. It took some tweaking on the program to get them back where I wanted (LTFT's at approx -5%).
Yes, it flows more air without the screen... BUT if it makes you too lean the computer will have to compensate and you might not get the results you were after. As with most anything the best gains are seen by tweaking the program for the mods you perform.
I would not descreen a MAF for a stock or near stock truck. Theres no real point to it. But, if you are like me and trying to get max airflow with Forced Induction... it MIGHT be worthwhile. Once again... not recommended without tuning.
And, yes, I am happy with mine.
This is a bit of real world results from a descreened MAF on my H2 with Radix and Cam-
I did not dyno before and after. I did not feel any SOTP gains (granted a couple of horsepower is not detectable with 6800 lbs attached to it). But I did see my Long Term Fuel Trims go about 5% leaner across a couple sections of the RPM range. The other sections went 2 or 3% leaner. It wasn't quite linear. It took some tweaking on the program to get them back where I wanted (LTFT's at approx -5%).
Yes, it flows more air without the screen... BUT if it makes you too lean the computer will have to compensate and you might not get the results you were after. As with most anything the best gains are seen by tweaking the program for the mods you perform.
I would not descreen a MAF for a stock or near stock truck. Theres no real point to it. But, if you are like me and trying to get max airflow with Forced Induction... it MIGHT be worthwhile. Once again... not recommended without tuning.
And, yes, I am happy with mine.
11-23-2005, 05:44 PM
#42
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I didn't think this would be such a hot button issue. You two really need to learn how to get along or at least ignore each other. This site is all about opinions right? WOO WOOO!!!!! 
BTW: Thanks for the opinions guys
BTW: Thanks for the opinions guys
11-23-2005, 05:55 PM
#43
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The reason its lot laminar, is because fluid flow is extremely dynamic. In order to even estimate it, you have to find out how laminar it is (or isn't) and apply a specific equation to find out its flow characteristics for that range of turbulence (Reynolds number). The formulas are VERY different too!
[sidetrack]Its really crazy and a big reason why computer simulation of fluids (CFD, computational fluid dynamics) is an extremely powerful too. some even say too powerful because people that don't understand fluid dynamics (myself included) can make some big mistakes with it. My fluids professor (major guru, does NASA rocket simulation and is accurate within 1%!) strongly advocates a masters degree with emphasis on fluid dynamics as a pre-requisite to using these programs.[/sidetrack]
I have a quick question though,
Is your screen before or after your blower?
the velocity of your air pre blower will be much higher than post blower assuming similar cross sections.
(conservation of mass. if its denser going out, the less dense air has to be moving much faster coming in). I'm going to guess the "out" also has a bigger cross section making the "in" even faster. Turbulence increases with fluid velocity.
obviously, the less turbulent, the closer they will be to the original "screen" readings.
Then again... turbulence also increases in density.
someone do the math, I'm lazy
[sidetrack]Its really crazy and a big reason why computer simulation of fluids (CFD, computational fluid dynamics) is an extremely powerful too. some even say too powerful because people that don't understand fluid dynamics (myself included) can make some big mistakes with it. My fluids professor (major guru, does NASA rocket simulation and is accurate within 1%!) strongly advocates a masters degree with emphasis on fluid dynamics as a pre-requisite to using these programs.[/sidetrack]
I have a quick question though,
Is your screen before or after your blower?
the velocity of your air pre blower will be much higher than post blower assuming similar cross sections.
(conservation of mass. if its denser going out, the less dense air has to be moving much faster coming in). I'm going to guess the "out" also has a bigger cross section making the "in" even faster. Turbulence increases with fluid velocity.
obviously, the less turbulent, the closer they will be to the original "screen" readings.
Then again... turbulence also increases in density.
someone do the math, I'm lazy
11-23-2005, 06:50 PM
#44
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Originally Posted by treyZ28
I have a quick question though,
Is your screen before or after your blower?
Is your screen before or after your blower?
Another thing particular to my set up is that, with the great weight of the truck and the hills in my local area, I only get about 30% throttle before I'm into boost. I'm in PE a great deal of the time. So with PE fueling taking over at that point my combo is less likely to show any negative issues (again all can be solved with tuning) that others may experience. I mainly get to reap the benefit of the increased volume that is allowed. With my combo maxing the MAF frequency relatively low in the RPM band (in the 4800 rpm area), this would give me more airflow than I was previously able to get.
11-23-2005, 07:42 PM
#46
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Originally Posted by treyZ28
PE? sorry, brain isn't fucntioning so well right now!
PE fueling mode is the power enrichment mode. A NA or FI truck hits it somewhere close to 0 vacuum. Mine kicks in a little early to be safe. This mode gives extra fuel.
07-10-2006, 11:45 PM
#48
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Originally Posted by treyZ28
The reason its lot laminar, is because fluid flow is extremely dynamic. In order to even estimate it, you have to find out how laminar it is (or isn't) and apply a specific equation to find out its flow characteristics for that range of turbulence (Reynolds number). The formulas are VERY different too!
[sidetrack]Its really crazy and a big reason why computer simulation of fluids (CFD, computational fluid dynamics) is an extremely powerful too. some even say too powerful because people that don't understand fluid dynamics (myself included) can make some big mistakes with it. My fluids professor (major guru, does NASA rocket simulation and is accurate within 1%!) strongly advocates a masters degree with emphasis on fluid dynamics as a pre-requisite to using these programs.[/sidetrack]
I have a quick question though,
Is your screen before or after your blower?
the velocity of your air pre blower will be much higher than post blower assuming similar cross sections.
(conservation of mass. if its denser going out, the less dense air has to be moving much faster coming in). I'm going to guess the "out" also has a bigger cross section making the "in" even faster. Turbulence increases with fluid velocity.
obviously, the less turbulent, the closer they will be to the original "screen" readings.
Then again... turbulence also increases in density.
someone do the math, I'm lazy
[sidetrack]Its really crazy and a big reason why computer simulation of fluids (CFD, computational fluid dynamics) is an extremely powerful too. some even say too powerful because people that don't understand fluid dynamics (myself included) can make some big mistakes with it. My fluids professor (major guru, does NASA rocket simulation and is accurate within 1%!) strongly advocates a masters degree with emphasis on fluid dynamics as a pre-requisite to using these programs.[/sidetrack]
I have a quick question though,
Is your screen before or after your blower?
the velocity of your air pre blower will be much higher than post blower assuming similar cross sections.
(conservation of mass. if its denser going out, the less dense air has to be moving much faster coming in). I'm going to guess the "out" also has a bigger cross section making the "in" even faster. Turbulence increases with fluid velocity.
obviously, the less turbulent, the closer they will be to the original "screen" readings.
Then again... turbulence also increases in density.
someone do the math, I'm lazy
08-19-2007, 11:05 AM
#49
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maybe people should tune with a map and everyone would be happy. 
i never understood why the gm and ford guys all love their maf's so much while the majority of car enthusiasts making big forced induction power run maps. even alot of the guys who are na use map over maf.
i never understood why the gm and ford guys all love their maf's so much while the majority of car enthusiasts making big forced induction power run maps. even alot of the guys who are na use map over maf.
08-20-2007, 10:21 AM
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Originally Posted by Rhino79
It's there to straighten the airflow coming in to reduce minimize false airflow readings, but on the cars with straight intakes, the screen isn't required.