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what color should spark be on a 59 235 ??
i have new coil wires points condensors plugs
and i get white not blue. not new rotor/ cap.
also what year did they change from shorter cap
to taller cap dist ?? my 49 has shorter and 59 taller.

The white color is probably because of the resister wires. The park should jump about a 1/4 in gap. If you are testing it by opening the points manually it will be stronger then if you are cranking the engine.

Color depends on what elements in the plasma and the intensity of the current. I think more bluish would be low current and more whitish will be more current, and maybe some more humidity in the air.

White is fine. If it's yellow/orange, not good. If it looks like static electricity type spark, no good/weak. Snappy and bright: good. Solid blue can be bad. Bluish white is the "normal" if there is a normal. Also, if it starts up and runs good you don't care what color it is.
Are you having trouble?

The conventional wisdom used to be "hot blue spark". That's impossible since radio noise suppression "resistance wire" came out in the mid-1950's. A weak-looking yellow/orange spark is pretty common these days, unless some sort of metallic wire is used. Metallic-core wire, either copper or stainless steel, is used in some racing applications, but the cost of getting that hot blue spark is rapid deterioration of distributor cap and rotor connections and rapid erosion of spark plug electrodes due to the high current flow spark. The radio frequency induction plays havoc with AM radios and TV signals in close proximity to a non-suppressed ignition system, also.
Jerry

So what is the takeaway for our buddy from Alaska? We got one poster saying blue is low current but the Professor says it is high current (no high resistance wire, cuz racing crews don't really care about Hank Williams sounding good on the radio)? We got one poster saying orange is not good, and the Professor says yellow/orange is to be expected today cuz folks now want to hear Metallica sounding good on the radio. So my takeaway is this, if your radio sounds really bad, you have "low resistance wires" and you should see a "blueish" spark. If your radio sounds good, you have "high resistance" plug wires and you should expect a yellow/orange spark. Current and Resistance are inversely proportional, remember ohms law, (I (current) = V(voltage)/R (resistance). Did I miss something?

Allen, you're on the right track. RF resistance wire can have an acceptable resistance of up to 1 K-ohm per inch, so a 24" wire can measure 24,000 ohms and still function properly. Instead of running "resistor" plugs that concentrate the resistance in a piece of carbon inside the porcelain, TVRS wire spreads it out over the entire length of the wire. The whole idea is to flow just enough current to jump the plug gap and the gap between the rotor and the distributor cap, without eroding the conductors in the process.

Does a firecracker make a louder bang if you don't blow out the match after lighting the fuse? Secondary wire resistance accomplishes the same thing- - - -it shortens the duration and intensity of the secondary current flow while still providing a hot enough spark to burn the fuel.
Jerry

I hope his takeaway is: