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Tuning FX Impact M3 further valve modifications


Nov 8, 2015
Karachi, Pakistan
    I was thinking about Impact mk1 model's goods and bads.

    Alongwith the plenum front part design I noticed that the valve seat was removable in mk1 models. Some people broke the seat many times, May be this is the reason FX opted for inbuilt fixed valve seat for later models.

    The old model design was good for tinkerers as they could play with valve seat design etc.

    Finally I found a valve housing of mk1 and converted it through exhaustive machining to work good in M3.

    Now the real game started that I wanted to play.

    I made a flat seating valve out of peek and also made the stainless steel valve seat with external O ring.

    My new valve seat is a bit larger in internal dia and the seating surface is almost flat like 15 degrease as opposed to fx OEM seats which are around 40 degrees.

    Just like my RAW HM1000X, this arrangement helped opening the valve with much less strike.

    Resultantly I got 60 more fps with .25 25 grain jsb pellets with previous settings.

    I understand that redesigning of valve and valve seats and converting to better materials and tighter tolerances helps in gaining efficiency and / or power.





    I’m late to the impact fanboy club (just got first m3 yesterday). After a night of shooting I can see what all the fuss is about. this impact is a major step up from my first fx and even my cricket or anything else. I’m just not sure I have the guts to tear into it like you did. But 60 fps is probably worth the effort. Love the pics and info.
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