J25GTi
Lifer
Mesh is more restrictive, its all about surface area, a larger surface area will suck more air in
Dyno print out.
- Thread starter Mental Mouse
- Start date
Mesh is more restrictive, its all about surface area, a larger surface area will suck more air in
Mental Mouse
Member +
So if I took the mesh off and left open mouth this would be restrictive too lmao, can't see how ya work this out! If that's the case why do drag cars use mesh on there turbo setups?
Mental Mouse
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Tip water through mesh an then tip water through a filter! Which one drains faster???
Mental Mouse
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I'm scratching my head trying to work this out now lol but all I can see a filter doing apart from the obvious is making the turbo suck harder which could well Cause boost creep? I can't see for one second that mesh is restricting the intake of air in comparison to a filter. I could well be wrong....Google 
Starlet_Sam's_Mum
Member +
Just ring Mike or Nick up, see what they say.
Just to add, if the thickness of the mesh wire is the same as the gap between the wires, you are covering half the turbo intake with metal. With a filter it has a massive surface area lets say 5-10x that of the turbo intake, even if it wasn't very permeable, which they are and even if the air was less dense than that of the hot air near your engine, it would still be able to let more air in.
But, you have cold feeds, so the air is much denser and if you buy a decent filter with a nice surface area, it's going to let in a lot more air.
Just to add, if the thickness of the mesh wire is the same as the gap between the wires, you are covering half the turbo intake with metal. With a filter it has a massive surface area lets say 5-10x that of the turbo intake, even if it wasn't very permeable, which they are and even if the air was less dense than that of the hot air near your engine, it would still be able to let more air in.
But, you have cold feeds, so the air is much denser and if you buy a decent filter with a nice surface area, it's going to let in a lot more air.
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Mental Mouse
Member +
It was nick that told me mesh it
Starlet_Sam's_Mum
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Well do that, he's your tuner. Did you get the mesh off him?
Mental Mouse
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No I used a large gauze from a tea strainer. Worked a treat
Typed this up so might as well post it now.
The bigger the filter the more air can be pulled through the filter due to the "bigger surface area" but that air can still only be pulled through the 35mm inlet diameter. Yes the bigger the filter the less restriction, however a meshed turbo has NO restriction as it's sucking straight from the atmosphere (open mouth). An easy test for this would be to turn on your vacuum cleaner with the pipe open, then the pipe covered with a rag. Hear the difference as the restrictive rag puts strain on the motor/turbine.
It sounds awesome when spooling up and gives a cheeky bit of chatter too
Typed this up so might as well post it now.
The bigger the filter the more air can be pulled through the filter due to the "bigger surface area" but that air can still only be pulled through the 35mm inlet diameter. Yes the bigger the filter the less restriction, however a meshed turbo has NO restriction as it's sucking straight from the atmosphere (open mouth). An easy test for this would be to turn on your vacuum cleaner with the pipe open, then the pipe covered with a rag. Hear the difference as the restrictive rag puts strain on the motor/turbine.
It sounds awesome when spooling up and gives a cheeky bit of chatter too
No I used a large gauze from a tea strainer. Worked a treat
Typed this up so might as well post it now.
The bigger the filter the more air can be pulled through the filter due to the "bigger surface area" but that air can still only be pulled through the 35mm inlet diameter. Yes the bigger the filter the less restriction, however a meshed turbo has NO restriction as it's sucking straight from the atmosphere (open mouth). An easy test for this would be to turn on your vacuum cleaner with the pipe open, then the pipe covered with a rag. Hear the difference as the restrictive rag puts strain on the motor/turbine.
It sounds awesome when spooling up and gives a cheeky bit of chatter too
If the mesh blocks say 30% of the 35mm dia, a filter will flow at least 100% of the 35mm inlet because the filter area is much greater.
Filter is more about protecting the turbo and engine from particles. Filter typically flows 6.03cfm/sq inch , rag does not.
Mental Mouse
Member +
I'm not after protection, it's derestriction!
Mental Mouse
Member +
At the end of it all mesh is less restrictive than filter!! But yes your very clever indeed
Starlet_Sam's_Mum
Member +
Get Nick to do a scientific test for the community.
Use a mesh for one of your runs and then use a relocated filter for another run.
Post the difference. Would be interesting.
Use a mesh for one of your runs and then use a relocated filter for another run.
Post the difference. Would be interesting.
Mental Mouse
Member +
Good idea is that, but the reason I meshed was so I could keep my aircon. Can't get filter on.
At the end of it all mesh is less restrictive than filter!! But yes your very clever indeed
If you want clever , try this -
At atmospheric pressure 14.7psi CID cubic inches displacement = 81.2836 (1332cc) 6.03cfm/sq inch material x 3456 = 20839 VEe volumetric efficiency of engine referenced to manifold conditions ( allow VEe = 1 [100%] )
[ This is not engine ve this is the intake Ve which can be up to 90% but use 100% which allows more flow for when the filter gets dirty. ]
Square inches of filter ( surface shape as a solid ) = ( pounds boost/14.7+1 )*VEe*CID*RPMmax/20839
eg: My cars Filter surface area openings would be = ( 20/14.7+1 ) x 81.2836x7500/20839 = 69.8 sq in surface area for 20 psi
I find this can be a useful formula ( from the mustang forums ) for filter size checking when higher revs , higher boost or larger turbo are used.
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Mental Mouse
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hell yh boy!! That's some equation right there haha
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