Boost gauge fluctuation 923A2

[FullSpecial]

I’m on my second gauge now, first one was an Autometer current one is a Hewitt Industries.
Both vibrate above 5 pounds of boost and it get worse the higher it goes. So at 30 pounds of
boost it’s bad. I’m using the pugged port identical to the starting aid port in the middle but at
the rear closest to the firewall. I have never seen boostgauges do this before and have a hard
time believing it’s the engine as it runslike a top. Anybody have any ideas?

 

[Tinstar]

Are you intentionally trying to make this thread hard to read?

 

[doghead]

Are you using rubber hose?

 

[FullSpecial]

Hard to read? Downright coherent considering last night………..
Doghead, no the plastic tubing in the kit.

 

[74M35A2]

May need a snubber. Several ways of doing this. One is to use a liquid filled gauge. Another is to put a restriction in the line at the back of the gauge, like a small orifice.

 

[Lukes_deuce]

I had the same problems with boost gauge on an older dodge cummins. Had to put a snubber on it. Just goggle it and find one that fits your thread pattern. Its reducer fitting to control the boost fluctuations. Or you could move the sensor to another place. Maybe on the intake manifold?