Redressing a controversial subject...

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Interesting idea. A conventional coil has about 100 millijoules of energy. Two coils in series have twice as much. Potentially a hotter spark. What that actually would improve is another question.

You could probably do it with one of those GM coil packs that they use to fire two plugs at once. On these both sides of the secondary are ungrounded. Put everything in series, use a points distributor and 24V supply and go to town. Have to figure out where to put the extra 12 battery.

Go for it, report back!
 
It’s like hunting pheasant with an Abrams tank. I’ve fired a 200 shot with points ignition and a standard coil. Please don’t tell me you actually think you need all this extra junk.
 
TT5.9mag said:
It’s like hunting pheasant with an Abrams tank. I’ve fired a 200 shot with points ignition and a standard coil. Please don’t tell me you actually think you need all this extra junk.
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You have just invalidated the entire sport of hot rodding!

Massive excess of everything is the American way!

The only reason I don’t hunt with a tank is that I don’t have one……hahaha
 
TT5.9mag said:
It’s like hunting pheasant with an Abrams tank. I’ve fired a 200 shot with points ignition and a standard coil. Please don’t tell me you actually think you need all this extra junk.
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im thinking that my best option is the chrome Summit coil with 60,000 volts for $30
 
Mike69cuda said:
You have just invalidated the entire sport of hot rodding!

Massive excess of everything is the American way!

The only reason I don’t hunt with a tank is that I don’t have one……hahaha
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Sorry to burst your bubble. If I put my Abrams up for sale I’ll contact you. :lol:
 
Brooks James said:
im thinking that my best option is the chrome Summit coil with 60,000 volts for $30
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The best option is to learn from others around you or at a track local to you. Walk around, ask questions, take pictures. If you’re an engineer and just like creating stuff like this, more power to ya, but the solutions to simple tasks are usually pretty simple. And firing a plug on a small shot of nitrous ain’t that difficult.
 
There are many 'White Papers' out there about coil ignitions and how you match the Coil winding ratios to what system you are using to charge and then discharge the primary windings.

I'd bet a MSD 6AL and a 'Fast' brand coil would jump a bigger gap than that Summit 60kv coil.

Dave999 said:
60KV coil??

What does that mean?

it doesn't mean 60KV spark
Because the voltage that jumps the gap can be as low as 6 KV with no fuel and low Compression
and 12-25 KV with compressed fuel and air in the gap
so if it fires at 25KV it will fire at 25 KV
if the plug fires at 30 it fires at 30
you'd have to open the gap up to something silly to get it to be 60 KV with a moderately sensible combination of CR and Fuel just not going to happen on a car that is streetable using a normal ignition set up
you might get 60 KV if you spike it with a CDI but again the KV level the spark is produced at is dictated by how hard tha gap is to jump and with all else the same it will still be 25 or 30 KV

makes no odds what it says on the coil

so that 60KV rateing is one of 2 things

1) the maximum voltage it can withstand without shorting out inside
2) the maximum voltage they managed to achieve using that coil and a huge gap at the plug that you would never run in a car engine.

CDI---very high voltage low current into primary can produce very very high voltage low current out of the secondary if you conspire to make the gap that needs to be jumped very large

in general though rateing a coil by KV is marketing rubbish
rate a coil by turns ratio
rate a coil by primary and secondary resistance
Rate a coil by saying perfect for use in a capacitive discharge igntion....

rating a coil by the effectiveness of the insulation used in its manufacture says nothing about performance its about as much use as saying this coil is RED this coil has a sticker with a lightning bolt on it


2 coils in series
one end sees 12-14 volts the other end sees 0 volts both coils then run on 6-7 volts if they are exactly the same type.
you have doubled the resistance in the circuit so you have reduced the current flow by half.
if it was 3 amps its now 1.5 if it was 6 its now 3
current flow dictates how fast the field grows to maximum. lower current flow means slower growing and smaller magnetic field
producing a not very impressive spark from each
if they are not the same type the voltage will be distributed across them in the same ratio as their primary resistance.

2 coils in parallel
you consume double the current when they are ON
current is usually limited by the coil primary resistance or the ballast or both
its limited so that you don't
1) burn out the points
2) burn out the blue box orange box chrome box etc
3) overload the wires

if the max current was 6 amps each coil will now try to allow 6 amps to flow
if the limit to this is external to the coil they won't flow the 6 amps they expect to flow
the magnetic field they create will take longer to grow to maximum
you kinda doubled the dwell you need to create a good spark
or reduced the operating rpm range by approximately 1/2.

if the switch (module/box or points) can flow 12 amps both coils will work as intended but marrying up the secondary output is not necessarily going to work. unless everything is totally identical.
and i wouldn't try it with my tacho connected.

better to get 1 single coil with a different primary resistance... lower
a switch (module or box) that can put up with flowing a current in the 6 - 8 amp range
and a ratio that produces a higher voltage spark
usually indicated by the coil manufacturer suggesting slightly wider plug gaps

HEI coil
low primary resistance 0.6 ohm designed to run at 14 volts and a suggestion of 40 or 45 thou gap at the plugs

Mopar coil low primary resistance 0.6 ohms designed to run at 8-9 volts with a plug gap of 30 or 35 thou

lower primary resistance means shorter necessary dwell to get to the magnetic field up to decent level hence improved RPM range

doubling up coils in parallel gives the impression of lower primary resistance
but that isn't the case both coils have the same primary resistance they always had
just the current has two routes to follow rather than 1

No real gain
if you want more than 1 coil look up wasted spark ignition you could fit a megajolt and use a Ford EDIS coil pack or 2 off a v8 or 2 I4 fords

Dave
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^^^^THIS!
 
Years ago on a Subaru Legacy forum about the Legacy Touring Wagon's with the H4 2.2 Turbo a few members were turning up the boost by almost twice. They were having issues of the cars just 'Laying Over' when it came up on boost. Over 200 replies from so many "Experts". They tried changing the Subaru coil pack, a 4 output coil, to a Mopar Neon's coil pack as they had a higher KV rating. It helped just slightly but not the fix.

Since the coil pack fires #1 and #4 together and #2 and #3 together the spark was trying to jump two 0.041" gaps and the high (boosted) compression ratio was blowing out the spark kernal. So after 200 replies and three members suggesting to just close up the sparkplug gaps from 0.041 to 0.035, POOF problems solved.

I solved mine by running 4 Kawasaki KZ1300 motorcycle coils fried by a MSD DIS-4 and gaps at 0.055"

If I were wanting to run a 300++ shot of NOS, I'd just do a Crank Trigger box firing 4 GM style 'Dual' coils.
 
If your really interested in blasting those plugs, buy a Magneto.
 
Brooks James said:
$$$$
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Yeah but life is short and money tends to run through one’s hands anyway. Go for the ride, take the trip and you can say I scare spark plugs to death. I can burn them to hell in a spontaneous combustion kind of way with my right foot (hot foot).
 
Brooks James said:
$$$$
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And if you do the mag, call the guy in Albany Oregon and buy a Mallory from him. I’ve used the Vertex, the Mallory and the MSD mags. If you aren’t going to need a bunch of retards and such the Mallory works best.

I’m not a fan of magnetos that don’t have an external coil.
 
How about a Tesla coil!

And I'm not being too sarcastic.

Might not be enough current?
 
I highly recommend the big yellow square-top Accell Super coil.
Mine operates from an easy running rpm of 500 to 7500 without a hick-up,
and car has gone 93 mph in the Eighth with it.
And has been on the car since 2002 at least.
If I pull the coilwire out during cranking, it looks like I could weld with it.
I make absolutely sure that my fuel system is NOT leaking; no joke. that coil will spark anything flammable on fire
I think I could set the neighbors grass on fire from a hundred feet away ........................ lol.

How much voltage does it produce?
Don't know/don't care to know.
How many amps?
Don't know/don't care, it sparks dead reliable from cranking rpm to over 7500, so what more could I want from an ignition system.......
Car won't go any faster with two of 'em, and even if it did, there are not many places to get into third gear at WOT, besides the track..................... which don't interest me.
But ya know, I run it off a relay, cuz my 32 YO Duster wiring harness (in year 2002) under the dash was getting a lil smelly on Day-1, lol.
Accell Super, the big one........ for the win.
I put mine out on the apron with a 30" wire. When I spend the night in a Hotel, 500 miles from home, I take the wire with me.
 
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AJ/FormS said:
I put mine out on the apron with a 30" wire. When I spend the night in a Hotel, 500 miles from home, I take the wire with me.
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I had a dummy coil wire I would put in place. If they see no coil wire they just might use a spark plug wire to steal it.
 
Kendog 170 said:
I had a dummy coil wire I would put in place. If they see no coil wire they just might use a spark plug wire to steal it.
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Great Idea, I never thought of that!
But I have multiple other theft deterrent measures.
Being a Manual trans car, theft is as easy as moving it down the road and putting it on a trailer, so, I didn't go overboard. Anybody can Hot-Wire one of these old cars with nothing more than a jumper-wire and a screwdriver............ so long as it has a functional coil-wire, lol.
 
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