Could you folks help me determine...

[dadsgreentruck]

...The condition of my 40 year old motor?

It's the 307 in my '70. The truck came into the family in the early '80s. As I recall, the odometer showed 17K. At the time I assumed it was actually 117K. It's now up to 128K (It spent about 10 years mostly sitting in my dads garage). Back then we had the heads re-built with new valves, added a steel timing set, and a cam that yields a slightly loping idle (don't remember what it is). On top we installed an AFB on a Performer manifold. Oh yes, and a Mallory dual point distributor with copper core wires. It was great fun to drive.

Fast forward 15K miles and 25 years. It just doesn't seem to have the "oomph" that it used to so I went out this weekend and did some diagnostics:

Compression: Cylinders 1-6 show 132-139 psi, while the 7 and 8 in the back are 119 and 121. Seems kind of odd the two in the rear would be that much lower since they are not adjacent.

Vacuum: fairly steady with a little wobble 14-15 in. at 850 rpm idle, leveling off at about 23-25 in. as rpm increases.

Advance: 10 degrees base. Don't know how much total I have as I don't have an adjustable timing light.

I also have a tick-tick-tick noise that I can't seem to determine the source. It seems to coincide with the wobble on the vacuum guage. I've also included a couple of spark plug pictures. They all look pretty much the same (Old bosch platinums). Reddish tan insulator with carbon depsits on the threaded end, though number 6 has some kind of tan colored build up on the ground strap. The pictures are fuzzy because I couldn't focus well that close.

I wonder if she could take a set of 305 416 casting heads?

Tim