Mark99GT

Check my math here….

I was looking at my MAF screen and thought about how much it would restrict flow, so I decided to calculate the area of the mesh…I got a total of 9.6211 inches for the area of the MAF (the circular area) by doing pi*r*r, which was 3.14*3.0625.

I calculated the area of the wires this way (and this is where I’m a bit unsure). The longest wire was 3.5 inches, the shortest was 1 inch; making the average wire length 2.25 inches. I then counted 70 vertical wires and 70 horizontal wires, for a total of 140. I measured the wire thickness at 1/100 of an inch. I then calculated the area of each wire. Which was 2.25*.01, which is .0225 inches per wire*70 wires equals 1.575 inches per side. Or a total area of 3.15 inches squared (1.575*1.575).

So...9.6211/3.15 equals 3.05, or about one third. Meaning, the wire screen eats up about 1/3 of the MAF area, which seems like a fairly large obstruction to me. Am I totally off here? Let me know if my math is bad. I’ve heard the screen is necessary for the MAF to work correctly. Does anyone run their car without it?

Disclaimer: I’m not saying you should run out and rip them out. But this is interesting to me.

Here’s a visual aid



[IMG]local://upfiles/5305/31AD97C9C62B4FB6A6555F209506EA30.jpg[/IMG]

yuengling910

that seems like a good amount of area, but keep in mind air is still able to flow through the screen. it's not like 1/3 of the air is being blocked at one point, causing the remaining air to flow around it. i doubt that removing the screen (which will probably mess up the maf) will allow much more air flow at all.

Derf00

Lol thats a lot of work to give you an answer,

1) can you run the MAF without the mesh? Yes.
2) is it recommended? No.
3) Why? Because that wire meshhelp to equalize airflow thus allowing the use of a single MAF wire to get a reading vs a series of wires to obtain an average.

01blkonblkGT

i have been running mine without the screen since i got the car back at the end of 2002. its been running fine. no issues with the screen removed here

cliffyk

I just mic'd the wire on mineat 0.008", and the effective diameter at 3.43"...[/align][/align]This makes the area of the whole screen = (3.43² * pi) / 4 = 9.24 in²;[/align][/align]I didn't feel like counting the wires, so going with your count and methodology (which is entirely close enough for back-of-a-napkin type thinking) of 140 0.008" wires, each 2.25" in length, I get 0.008" * 2.25" * 140 = 2.65 in² of wire;[/align][/align]So, the screen effectively reduces the area of the "hole" to 6.59 in², orthe equivalent of a 2.90" (73.5 mm) dia circle. [/align][/align]The stock TB is 65 mm (effectively less because of the butterfly shaft), so if we assume the turbulence ("straightening") of the screen is beneficial* then it sounds like the Ford engineers did their homework...[/align][/align]Obviously (since I could just jump up and mesa sure it), my screen is not "in" (I am running the OEM air box and tube). I believe it's absence explains thesomewhat "lumpy", but not enough to matter,idle I experience.[/align][/align]-----------------------------[/align]* - The screen is there to straighten the flow through the MAF, and it does do this although I have not found it to be 100% needed. However, my car came to me with a really lame eBay CAI which had a 3" ID K&N clone filter and MAF adapter--with no screen the idle was quite lumpy and there was a lot of surging at lower speeds and loads, puttingone in fixed most of this. (The eBay crap was replaced within a week of my getting the car).[/align]

BraMas

I can't believe you guys actually wasted your time figuring out if that stupid mesh screen is needed. I also can't believe I spent time trying to understand anything you guys where talking about.

Here is a little tech article I found after reading this post. Yes it deals with GM but it's the same concept
MAF Myth here

Mark99GT

I was thinking about that after I posted this. You hit the nail on the head. I should have figured it as a circular area not a square and I would have had my anwer.The "hole" is still bigger than the stock tb, and with up to a 75mm there shouldn't be any adverse effect on air flow. I guess Ford did do their homework...

cliffyk

Not a bad article, some misinformation but not a lot (it's actually the current [amperage] needed to keep the wire hot that is measured)--the faucet aerator is a very good analogy...[/align][/align]All that said however, if the airflow into the MAF is reasonably straight because of a longish run of straight pipe before the MAF or because of an even flow into a good air horn (the OEM airbox is actually pretty good) the screen is not needed--unless your air filter will pass small nuts and bolts, or you are klutzy enough to "drop them in there" while working on the engine...[/align][/align]

Cornbread01

yea what they said math yea

BraMas

Yea that faucetanalogy made everything make sense.