At 13:12 2004-06-26, you wrote:

 
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This version reduced the altimeter error to 50-70 ft high and the indicated to around 7 KTs too high.
 
Not sure what to try for the next version.
 
Bill Eslick
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I'm surprised your ASI is that far off Bill.   I'm using the same pop rivet static ports (one each side) and the ASI has been accurate to within 2 mph or less at all speeds I've checked. 
 
Tracy
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Tracy,
 
I am very sure the problem is static, since the altimeter reads high and two ASIs read exactly the same (Dynon and round-dial).
 
Since I have already plumbed in a static probe (removable), I will continue to investigate probe shapes until I get a winner.
 
Bill

You guys are comparing an RV-4 with an RV-6 (I know, you knew that).  The -6 is known to have some flow separation aft of the bulkhead where the angle changes along the side. 

Bill, throw some yarn tufts in a grid on the side around the static port and forward past the bulkhead where the angle changes and go get some air to air pics.  You should see a difference in the air flow patterns.  This may help you pick a better location for the static port.

Mike McGee, RV-4 N996RV, O320-E2G, Hillsboro, OR
13B in gestation mode, RD-1C, EC-2