I'm guessing weak/cracked valve spring(s) and they are getting worse.

Have you found the problem yet?

No, but the situation has improved. Turns out one of the ignition modules I swapped in to replace the Crane box was faulty. Tried a V8-24 Module and it got better. Next up is the V8-20 off a HP 500. I may have got the rockers adjusted a smidge too tight. I suspect that may be where a few of my RPM have gone. Right now it runs clean up to 4800 and fails to build RPM past that. Boost is normal, compression and leakdown fine.

Do you have the non-adjustable rockers? If so what torque did you use?

Funny thing after I started reading your string my Checkmate started do a similar thing. Maybe its bad ora. Going to work on my problem today. I hope it might be a loose wire somewhere.

A cracked valve will do exactly what you have described. You will also not be able to get to full rpm.

Here is what I did. Jumped directly from + Bat. to + Coil and solved problem. I figure long small gauge (old) wire all the way to dash and back to coil is sucking Vs/amps. Plan to put key relay near coil to solve problem. Will post results.

I meant to update this. The HP 500 module solved my problem. Only minor issue left is a slight stumble when trimming at WOT. I am also pursuing the relay to activate clean 12V to coil. Might be a lot easier than running all new wire from harness to dash and back. Should have been built that way to start. If I go this route a blocking diode will be used across the relay coil.
http://www.bcae1.com/relays.htm

Baddog,

Tell me about the blocking diode. What is it for and were does it go? I was just going to use the relay near the coil.

Followup: I used the ling in your above e-mail "I see" said the blind man.

I have two relays Hella and PIAA from off road light systems I used. They both have built in diodes and the Hella has a 10 amp fuse. These are way over kill but I have them and they should last.

Rocket Science
 

Oh BTW "I" figured this out after several weeks of having this problem and wrapping wires, separating wires, replacing wires, cleaning contacts (Baddog you know the drill) I finally asked my dad about the problem. Who is an aeronautical engineer (rocket scientist) he said immediately jump from +bat to +coil, if the stumble goes away take the jumper off and install an ignition relay between the key and the coil near the coil.

Never be to proud to ask good ol' dad for help:rolleyes: .

Hey baddog here's to solving the problem :ernaehrung004:

Have you hugged your Dad lately?