Let me first explain what all I have done to help better diagnose the problem: The car sat for about 2 years because I was getting no spark (due to the MSD ignition box) and I had a leaky rack and pinion and some tranny trouble, but before the msd box went bad it ran fine. So I pulled the engine ( a 460) this winter, took off the heads, manifold, timing chain cover and
oil pan so I could repaint them. I replaced the gaskets to those parts and put it back together and dropped it back in the car. I went with a new "Summit" brand ignition box and also bought a new Crane Cams distibutor to replace the MSD one and a new coil. My trouble now is, cylinders 5,6 and 7 are not firing. The header tube to #5 is warm to the touch, 6 and 7 are cold and 8 is hot. So far, I have messed around with the timing (which doesn't change anything with those cylinders) replaced the coil (again), swapped plug wires and plugs with good cylinders, rotated all wires around the cap a couple of times and re-adjusted timing. I have good spark to all plugs. I did a compression test of all cylinders (all were good), then tonight I just did a leak down test just to be sure it wasn't anything going on with the valves or anything. And yes, I have checked to make sure the wires are in the right order, multiple times.
I am fairly certain that when I rotated the plug wires around the cap to different posts, that should eliminate problems with the ignition system, right? I am not 100% sure on an HEI system though, so correct me if I'm wrong. Since it is carbureted and one of those cylinders (#8) on that head is firing they should all be getting fuel, right?
I don't know what else to do and am totally stumped, so any ideas are welcome. Thanks. (sorry about the novel)
Need help with some cylinders not firing
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