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What is the firing orrder???

Does the spark plug wires run thru a STEEL tube or are the wires simply dangling out in space as most engines do????

Usually the valve lifter will spin faster when the valve clearance is too small. Tight valves will also make for a very "skippy" engine, especially when it is hot. Even before the valves burn it will make the engine run oddly because it is a defacto change in the valve timing, ie. the valve will open too early and close too late.

Firing order is correct and the wires are not shorting out. I put the plug against the block and I was getting a very good spark.

Let me repeat the questions:
1. What is the firing order.
2. Do the plug wires run thru a metal tube or are they just floating out in air as do most engine plug wires???

ok. i went and looked up the firing order.
Double chek to be sure if this is right for your engine:

1 6 2 5 8 3 7 4.

CHECK to make sure that #7 wire is NOT touching the #4 wire AT ANY POINT.

Might want to go thru the ENTIRE firing order to make sure that no plug wire is touching THE NEXT plug wire ready to fire.

IF the wires run thru a metal tube then it does not matter if the wires touch each other.

There needs to be AT LEAST 1/4" clearence between the wires of any 2 consecutively fireing cyclinders.

Phil,

For what it's worth, probably very little, Wade had an issue with his '37 Super 8 a while back when he had a great deal of trouble tracking down a miss. After checking/testing/eliminating/replacing "the usual suspects" he ended up stumped. Then on removing the valve covers, even though all looked to be OK, Wade found that one of the valve springs was broken. A little different to your 120 in that the Super 8 has double(inner and outer) valve springs, but maybe worth having a real close look at #4 while the engine is running?

Mal that was what I thought could be the problem so I took a good look while the engine was running. The only thing I questioned was the rapid spinning (compared to the others) of the valve.

"It doesn't seem to be firing"(#4)
Do you mean not making as much power instead?
It's not clear why you suspect this cylinder?
Firing can be easily checked. So if it's not firing, as you say, it's an ignition issue that needs fixed and is not puzzling. {I like to take the conductance type timing light and put on the affected wire and check the pattern of light flashes. Or you need an analyzer.}
If ignition is good, checks to spec, then it's something else.
There's alot of reasons beyond that, so you need a methodical approach.

Simple test. Pull the plug wire and plug and hold against the ground metal somewhere and see if it is actually firing the plug. Or use an inline spark tester. Then at least you'll know you're getting spark.

If you are not, then you know it's in the ignition system somewhere: Plug, Wire, Distro, etc.

If you are getting spark, and you are sure the firing order is right, then you can pull the valve cover and observe the value action on the cylinder 4 to see if anything is wrong.

Thanks for the suggestions but I already did the spark test ( I have spark) and pulled the valve cover and all looks OK in there. I'm going to ponder everything for a while then get on it again.