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Hey fellas...just a quick afm question...the afm in my 32 just shat itself yesterday and i managed to get another one off a mate just so that i can drive the car...problem is...the wire screens on both ends of the replacement afm have been removed...mate did it to improve flow...i was just wondering if not having the screens there would cause any problems? be it with idle or air/fuel mixtures...cheers...

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there is an article on this in the latest HPI and according to them is better if you dont have the screens in there at all.

but at the same time they recommended moving the AFM to after the cooler.

Are they seriously printing that shite - those f**king idiots. Lets remove the screen for an extra pooftienth of a HP. I know removing the screens on nissan based airflow meters doesn't make much difference to the fueling and ignition but its so not the case with other manufactures where the screen is there for straightening purposes.

there is an article on this in the latest HPI and according to them is better if you dont have the screens in there at all.

where does it say that?

quote from HPI - page 107

picture 9 - "airflow meters that have been 'de-screened', such as this VG30 unit, are often more prine to pulse problems due to their large cross-sectional surface area"

page 108

picture 11 - "you can see how much surface area of the airflow meter inlet the wire gauze takes up. Adding an extra "screen" then reduces the inlet size to the engine dramatically, and costs you power in the prcess. Don't do it!"

Thats what I thought also ben...

I also had a couple noticable issues when I removed the mesh on mine.

1. Idle wasn't as stable

2. When coming off hard throttle the car would act as if I had stabbed the accel. quickly causing the car to give a little lunge forward 'just' after I jumped off the throttle.

It may have been just me but I swear spool improved a tad, but it may have just been running a tad richer as mine was (with the mesh on) running in the mid 13's until around 4000rpm. As with flow the center flows quicker, removing the mesh would only increase center airflow.

I don't know a whole heap about flow dynamics but I do remember it went something like that. :wave:

Thats what I thought also ben...

I also had a couple noticable issues when I removed the mesh on mine.

1. Idle wasn't as stable

2. When coming off hard throttle the car would act as if I had stabbed the accel. quickly causing the car to give a little lunge forward 'just' after I jumped off the throttle.

It may have been just me but I swear spool improved a tad, but it may have just been running a tad richer as mine was (with the mesh on) running in the mid 13's until around 4000rpm. As with flow the center flows quicker, removing the mesh would only increase center airflow.

I don't know a whole heap about flow dynamics but I do remember it went something like that. :O

Yah i had a problem with my old custom made AFM being too close to the turbo causing very strange problems.. gets super rich after slight spool. :)

Made a nice split intake pipe now. looks pimp.

i have a Q45 im about to install, unfortunately someone removed the rear screen ... :O

seems likely according to said article in HPi, that the rear screen would dampen the affects of reversion on the AFM.. while the front screen would be doing what everyone believes and regulates the airflow into the AFM...

As I had a couple of small issues that annoyed me I bought some mesh, cut it to fit and glued it in. Looked like a new one. :O

I was a little worried the superglue (was the most expensive I could find) would let go due to the heat but after several checks and many kays it hung in there perfectly fine.

As I had a couple of small issues that annoyed me I bought some mesh, cut it to fit and glued it in. Looked like a new one. :O

I was a little worried the superglue (was the most expensive I could find) would let go due to the heat but after several checks and many kays it hung in there perfectly fine.

would you think silicon would work as well?

where abouts did you get the fine mesh from?

might see if there are any issues and try it out if there are.

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