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hey guys,

i've read eliminating negative boost ... ( googled it )

sounds fair that a mesh causes air to turn into small particles after its gone through the filter to enter the intake piping...

SO by removing the mesh is less restriction thus more air flowing in

wat do u guys think it will do to the car and how will the ecu react?

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https://www.sau.com.au/forums/topic/138144-afm-mesh-removed/
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What you said up the top is simply incorrect.

How can the mesh break the air up into little particles.

Think of the air as a fluid. Imagine if you put a mesh into a flowing stream of water. The water flows around the little pieces of the mesh. A mesh that thin hardly affects flow.

Any restriction caused by the mesh is so absolutely minute in the scheme of things.

Have you had a look inside the factory flexy pipe on the turbo? that would cause more turbulence than the afm mesh.

Hell, silicon pipe joiners would cause more turbulence on the edge ofo the metal pipe than the afm mesh.

Edited: further clarification + spelling mistakes.

Edited by MANWHORE

actually, the comoodore boys (inc myself) tested this. no gains to be had what so ever. it actually made some cars run wierd and stuff. our thoughts is the mesh is there to "straighten" the air to help the ecu read the airflow better.

I think it's safe to say that this is settled.

Summary:

1. Any reduction of restriction by removing mesh is negligible.

2. There is a good chance that issues will arise if the mesh is removed, and by refernce to point 1, it would be stupid to do so since there will be no gains anyway.

The biggest annoyance I found was the surge and overfueling pops that followed jumping off the throttle. It appears the mesh also helps prevent the air that is dumped out of the bov from passing the afm in reverse.

So.. you're saying this mighty magic mesh is a one way diode sorta thing eh? heheh... :P

So.. you're saying this mighty magic mesh is a one way diode sorta thing eh? heheh... :P

LMAO... yer I guess.

I'd better explain it a bit better though.

With the mesh removed; boosting hard with say half throttle then backing off enough but still on the throttle so the BOV lets go; at this point the car would have a single surge jerk type feel.

With the mesh there; it simply doesn't happen. I usually had the jerk/surge when driving up a hill and partially backing off (flagstaff hill for example).

Removing the mesh I noticed ZERO difference in fuel economy (consistent 470km's to ~50litres). Just that little annoyance when coming off the throttle.

I siliconed the mesh back in, felt much nicer. :O

remove the mesh on all of my hotwire afm.

never any problems, just reduced inlet restriction.

this includes all sorts of configs, both na, turbo, airbox, pod, rb30e, rb30et, rb30det, rb25det

with the mesh removed a little more air gets through unmeasured, so your open loop mixtures are a little leaner, and you get a little more timing when in both open and closed loop.

the mesh is a bigger restriction than a standard paper element filter.

All the mesh does is break up big incoming swirls and eddies into small swirls and eddies. If your airbox and upstream pipework is reasonably well designed the mesh does absolutely nothing. Removing it offers no advantage.

But on some cars, the air flowing into the flow meter may do funny things at certain particular speeds and loads. Removing the mesh may therefore sometimes cause some strange problems to arise that were not there with the mesh fitted. But not on all cars.

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