71 340 running bad
Everything is new. Car makes no vacuum. If you put it close to where it is supposed to be timed it quits. 4972 thermoquad rebuilt by harms, seems rich? Car gas fouled two sets of plugs just trying to keep it running. Help please
assuming all the vacuum ports are either employed or plugged, and that your secondaries are fully closed, that your brake-booster is not sucking air, that your PCV system is correctly plumbed and working properly, that there is no manifold vacuum in the crankcase, that the metering rods are staying down, and that you have proven your TDC mark is at least close;
At Idle, your engine will respond well to massive timing, just start it up, and without regard to the numbers, just pull in the timing as much as it likes. You will know that it is liking it by the fact that the idle speed just keeps going up. As you go, keep backing off the speed screw to keep the idle speed in check.
When you reach a point than additional timing does not produce additional rpm, stop and back up to the last adjustment that did. Now you can read the timing. If you have a Multi-strike ignition, you will need a compatible timing light.
If the number you get is greater than 90 degrees, you are on the wrong Plug-wire; back up/go forward, one cylinder in the firing order. Keep trying wires until you get one that reads about 25>35 degrees. Now yur on the right wire.
Do not drive it like this.
If you already are on the right wire, and getting a number in that range, then; shut the engine off, take the plugs out, and with the engine still hot, see if you can rotate the crank manually with a regular Johnson-bar.
If you find it to be extremely difficult, yur gonna have to figure out why and my guess would be that the ring gaps are too tight. To prove it rip the valve covers off, remove the valve gear, and try it again. With the gear off you no longer have to fight the valve springs, so if it still turns over real hard by hand, then sorry, I would be taking that engine apart. Another symptom of too tight rings at a normal timing of 14 to 18 degrees is that all that ring-friction tends to drive the engine into overheating or at least very high coolant temps.
While the gear is off, this is a good time to find split overlap, and see if it's at least close.
This happened to me. I added ~.004 to the top ring, and ~.002 to the second, and that was all it took. Yeah it was a PITA, but I was out of options. That engine got a whole new personality.