K valve leakdown

I have just installed a new style k valve on a 406 sm bl chevy, 8-71 15% over. the idle poppet is set at 4 psi. I had to move arms to get proper movement of barrel valve, I set the butterflies and inlet air pressure was at 100 psi adjusted to get 78 on leakdown gauge, however at wide open throttle is only registers 95 is this telling me i have adjusted something wrong.if i reduce inlet pressure to 60 psi i get gauge to read 100

 

are the arms parallel of each other when closed and wide open?

 

both of the arms are almost parallel in both positions there is olny a slight difference. i am unsure if maybe the barrel valve needs to be repositioned

 

How about the length of the arms? some arms have multiple holes for bolting linkage too? when the barrel valve is wide open and the blades are wide open both arms should be parallel.

 

i have unhooked bottom arm and moved it by hand and still cannot get 100% the only way to achieve 100 is to reduce inlet pressure to 60 psi

 

in addition to what Bruce is saying make 100% sure you are putting 100 LBS at your gauge. The air compressor should have a full head of air and not be weak. Make sure the Leak down tool you are using is callibrated right. I bought a duall gauge tool off a snap on truck and it was way off. I borrowed a big single gauge from a buddy and it was off by 25%. Sounds like a gauge problem to me. If its a duall gauge both sides must be at 100 lbs equal and a single 100. Not trying to throw you off but even new tools can be off even when you are doing it right

 

If you're reading 78 on the second gauge, that would be 22% leak into the motor. You need to see 22 on the second gauge to get 78 leak to the motor.

Also make sure your idle ck is capped off...

 

????

What % of leak down should you have on a bae alky engine? roots 14/71
Thanks

 

Dam it Mike it's .040 jet. google leak down and see for yourself.

 

I sorry mike