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what a terrible rule lol

id take the mesh off the back of the AFM, honestly whats that filtering?

It doesnt filter anything. An air filter does that :dry:

It just breaks up any turbulence that might have been induced by the shape of the tubing from the filter to the afm

-D

I ripped the mesh out of both of my AFM's and made them a straight though pipe, but that's only cos they do nothing on my car anyway. :dry:

Edited by DSTROY
It doesnt filter anything. An air filter does that :dry:

It just breaks up any turbulence that might have been induced by the shape of the tubing from the filter to the afm

-D

the first mesh doesnt do that?

maybe replace it with blue mesh, it will get 11% for sure then

Why all the hate dude? :D And didn't you know blue mesh is good for 10rwkw? :P

Well, did some digging. Yes the mesh does restrict flow, but only marginally. And it does so to disrupt laminar flow and induce turbulence. It can also change the way the AFM reads, and alter the load figure the ECU uses.

Why all the hate dude? :D And didn't you know blue mesh is good for 10rwkw? :P

Well, did some digging. Yes the mesh does restrict flow, but only marginally. And it does so to disrupt laminar flow and induce turbulence. It can also change the way the AFM reads, and alter the load figure the ECU uses.

Yeah, what professor ruebenstein said

-D

All i saw was the "11% More Flow By Removing The Mesh" i thought it was a stab at Ruby...had another look then saw the rest :D

It doesn't really say anything about more Performance, just more flow through the AFM, which in turn could equate to more performance. I would still leave it on though...even though i am getting rid of my AFM shortly for a MAP.

All i saw was the "11% More Flow By Removing The Mesh" i thought it was a stab at Ruby...had another look then saw the rest :D

Oh don't worry, the pack of bastards are still having a go at the mighty blue mesh :)

:P

The Airflow meters with honeycombe were to ensure that the flow was even and could garauntee an accurate reading. The mesh ones however are a safety barrier. Want to know how much difference it will make? Take the mesh off and pour water through the mesh at a constant speed (under pressure of course) then remove the mesh and see how much water you can pass though in the same amount of time. Air flows exactly the same way as water, essentially air is a less dense fluid. I'm betting you can get the same amount of water through both times as the surface area of the wire itself is minute in comparison to the area of free space between the mesh. Yes, it will cause turbulance but more so if it was being forced through the mesh in a push situation, but being a turbo car it is under suction and that air is under a pull senario.

Want more air? split the intake line off between the AFM and the pod and make a 'Y' piece to have two pods. Once again.. what gain if any except that there is now double the surface area available to draw air from but still the same anemic engine and mods after that.

End rant!

Edited by Stagstock
Want more air? split the intake line off between the AFM and the pod and make a 'Y' piece to have two pods. Once again.. what gain if any except that there is now double the surface area available to draw air from but still the same anemic engine and mods after that.

End rant!

Or, just ditch the 60mm afm's and upgrade to the 80mm z32's :D

-D

interesting topic.

ive found after getting my new car, that mitsubishi maf sensors (afm) as much more temperamental with smooth air flow and turbulence. generic pod filters make the mitsu afm read rich and often the car will stall. to overcome this the mitsu guys run a long intake pipe, where in theory, by the time the air is at the sensor, it will have aligned. or (which are now available) u can get specific pod filters with work with the mitsu maf sensor and keeps the air aligned, to prevent the circular motion of air generic pods create.

so whats this got to do with skylines? well i guess all cars are prone to this, just nissans are a lot more robust and the effects are minimal.

The problem with the mesh isn't the reduction in flow it's more the pressure drop that it induces.

Compressor flow is dependant a pressure ratio (when you look at a compressor map the numbers on the LHS of the map) meaning that the flow output increases when the absolute pressure presented to the compressor inlet is increased. What the mesh does is reduce the pressure in the intake tract before the turbo and therefore reduces the compressor efficiency.

Having said that, there are a lot of reasons for the mesh to be retained, the main one being the laminar flow reason mentioned above and it is required for the AFM to function correctly/efficiently. And really if you want to increase compressor efficiency by reducing pressure drop then you should be lokoing at a MAP based ECU and even then you will find that the air filter produces a bigger pressure drop that the mesh on the AFM.

Oh don't worry, the pack of bastards are still having a go at the mighty blue mesh :P

:)

Ruby I dont hate the blue mesh, I just hopped on the comment bandwagon

Edited by sapphiregraphics

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