Well, I bought the car a few months ago, and according to the guy I bought it from, the engine has about 500 miles on it. He had the 440 built and dropped it in to replace a 318. He said he put some miles on it to break it in, but started having trouble tuning it. Got frustrated and pushed it into storage, where it sat for 20 years.
I'll pull the valve covers off today and have a look.
My LD tester is a NOS Harbor Freight model - seems a bit better quality than the newer junk, but maybe it's just older junk...LOL. I like the idea of installing a valve to control the air flow. What I did was zero the test gauge at 30 psi and go from there. Once connected, I referred to the second gauge which shows leakage, and thats how I got my numbers.
Regarding the method of unscrewing the rocker shafts, help me understand. Wouldn't the air pressure also push the valves shut, causing a false reading? This seems like a much easier method since you don't have to fuss with finding TDC, I wonder why more people don't do it this way. I also may not understand what you mean...
Edit: When I tapped the valves, I tapped pretty lightly. Light enough to where I don't think I was even overcoming the springs. I just thought that maybe a little bit of energy would settle the valve, if that's what it needed. Hopefully that sets your mind at ease a little...haha.
I have a newish MSD Blaster 2 that I had installed briefly, and while that may not be exactly when I noticed the problem, the problem definitely existed using that coil.
