Manifold Vacuum Experiment

I gave the truck some new sparkum plugs this mornin. Gapped um at .045. Remember, I'm running the GM big cap sho nuff HEI and it's pretty hot. I also did a compression test. Although I pulled and replaced one plug at the time, so I did not remove all the plugs so the engine would spin faster, nor did I block open the throttle. Yeah, I'm that lazy. Got 130-135 across the board. I just "guess" with all the plugs removed so the engine would spin faster and the throttle blocked open "by the book" it might see 140 "or so". Really not terrible for a low compression engine and lumpy hydraulic cam. I'll get some on the road vacuum readings soon. I haven't forgotten.