Okay, you electrical whizzes jump on this. If you "Y" the wires from the distributor cap to two plugs will both fire equally or will the current go the path of least resistance and just fire one? If no one knows I will use the set up we use to check magnetos on, only double the length, and answer this myself. A radical project is in an embryonic stage. I know Suburbans in the 70/80's had front and rear a/c units and still just used one compressor but this may be comparing apples to oranges.
Least resistance My money's on the one spark least resistance, even if you were to get the occasional twin spark they would be weaker than one.
Ac rules I'm afraid fluid dynamics and electrical rules are completely different, you can do things like split the load off a compressor but not with a spark.
I'm no whiz, but I am an expert (see below). I agree with Brit on one plug firing. Which plug that is may even vary with load, amount of charge in the cylinder, temp, etc. What are you up to Evan? Expert: Ex - used to be spurt - a drip under pressure
Apples and Oranges It will travel the path of least resistance and find ground that is what it wants to do THe A/c System you reference is pressurewhich is high on one side of the expansion valve and drops its pressure through the expansion valve(and its temperature) totally different dynamics Bill
I've never felt moved to experiment on anything like this,but check out the F**d ignition system and find out how two plugs per cylinder fire at the same time on some of their four cylinder engines. If the spark you suggest didn't find the path of least resistance and fire a plug on the wrong stroke I'd think it could possibly have very negative effects.
B29 Check out a b29 with four engines 36 cylinders each and two plugs per cylinder all the plugs in the fron were fired by one Magneto and the rear plugs fired by a second Magneto Just so happens I was cleaning and checking spark plugs today , Aircraft engine spark plug have dual electrodes and are tested in a pressure vessel to simulate compression in the cylinder, and even though they are evenly gapped one is off but a smidge and it will not fire until the other has worn away enought make it the path of least resistance Bill
Definitive answer there, Bill. Guess I brought this question up at an opportune time with you cleaning and testing. Ken, Cadillac and Marmon also made V16 engines but I'm glad you posted the picture showing the twin contacts on the rotor. I was wondering how they got enough coil saturation with just 22 1/2* between lobes on the breaker cam. I have contacted a MSD guru and it seems a crank triggered pickup with coil on plug will handle many firing impulses with no loss of spark strength. Federale, I looked at the twin plug arrangement on an older Nissan 4 cyl and they use what I would call a "stacked rotor", two rotors inside one cap, one on top of the other. Bill Hanlon, the potential project is a V16 1940 LaSalle using two 400 sbc end to end. Dusty's Rod Shop in Leonard, Texas (8 miles from me) has a 59 El Camino with two 350's side by side and with stock front fenders/hood/grill. Fitted with a Buick firewall, recessed for the straight eight engine, and the LaSalle's l-o-n-g nose there is room for the much prettier end to end set up. The fellow commisioning the project is ready to jump if the gathered data will support feasibility. I told him an 800ci (13.1 L.) heavy car is what everyone needs when gas is predicted to be near $4 again this year.
Trivia Marmom was founded by one of the Marx Bothers ,Zeppo Marx ( went and did the Wiki thing on it to find which one) and thier products are still used today, Marmon Clamps as they are called are used on turbo housings and turbo exhaust hookups also called V-Band clamps Bill http://en.wikipedia.org/wiki/Marman_clamp
Too many cylinders You do like a challenge Evan, why not go for a V10 viper engine and save a lot of headaches