ring break in time

Pishta, I think you are on the wrong track. A guide, in my view, would have to be so bad that you could easily wobble the valve in there by hand and see it, before it would leak enough to not fire. I think you have another issue, like an intake leak, etc.

"I aint there" so just some wonderings...........

1....This efi or carb? That alone could open up all sorts of stuff. Again, vacuum, intake, etc leak
2...You ever run a leakdown? Even if you don't have one, you can put air into a cylinder, either make a fitting from a plug or you can buy cylinder/ air fittings cheap OR----remove the schrader from your compression tester and use it to inject air

3... You can easily make a leakdown tester from a compression gauge, an air regulator, and a few pipe fittings. You really only need one gauge. I'm assuming you have a hose type compression tester with a quick disconnect setup? Put the gauge on the downstream side of the orifice which you can make, and set it by unplugging the hose, which blocks airflow by closing the connector, and set the gauge for either 80 or 100. Then screw the hose into the cylinder at TDC and plug the hose into the made tester.

Your "path" is air hose--regulator--tee. One branch of the tee gets a quick connect nipple to fit your compression gauge, the other tee branch gets an air coupler to fit your compression gauge hose. Figure a way to fit the will be orifice between the regulator and tee. Drill it for .040" or close as you can, or find a jet like Holley about there, and braze / solder it in It will not be "aircraft accurate" but it will give you comparable results.

Is there ANY chance you are misreading the spark situation. Any chance there is some sort of distributor / cap/ wire problem that you are missing? Timing? Firing order?

Any chance the cam is flat?

You can bounce the valves by tapping with a hammer and a piece of wood, and that will give you a clue "if they are sticking."


Take a really REALLY good look at the intake system. Stick an unlit LP torch in there around that port and see if "anything"