Incorrect airspeed indication.

[Wpsullivan99]

Just finished up fixing a bunch issues on my Acroduster 2. One of the issues was and extension of the pitot tube about 8 inches in front of the leading edge. Previously had a one inch stub sticking out of the wing. At 2500 rpm I’m indicating 125 mph. GPS shows avg of 105 mph. The tubing I extended the pitot tube with is aluminum 1/4 outside diameter. Question I have is what size opening should I have for a correcting on the air speed indicator. I believe its less noticeable at slower speed which would make sense to me. That Cessna has a opening of 1/8 inch. Thanks for any information provided.

 

[Dana]

 

[PittsDriver68]

 

[TFF1]

 

[Wpsullivan99]

 

[Wpsullivan99]

 

[EAABipe40FF]

 

[PittsDriver68]

 

[wanttaja]

 

[PittsDriver68]

 

[mbourget]

 

[StinsonPilot]

 

[PittsDriver68]

 

[Wpsullivan99]

 

[DennisV]

 

[EAABipe40FF]

 

[wanttaja]

 

[DennisV]

 

[wanttaja]

 

[Wpsullivan99]