Ignition boxes?
02-04-2019, 09:34 PM
#1
Ignition boxes?
Got the 57k volt coil from hypertech, got ,msd wires 8.5s, got an msd cap n rotor, was wondering what the highest box is to go with? Ive used the 6A and 6AL, i want something with much much more power, if anyone has any ideas let me know.
02-04-2019, 10:56 PM
#2
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Join Date: Nov 1998
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Re: Ignition boxes?
The voltage required to fire the plug is determined by the plug gap, electrode condition, cylinder pressure, and A/F mixture, typically 15-30kV for a normally aspirated Street engine. Using a coil capable of 57kV will not raise the voltage at the plug before it fires. It will not produce more power.
The “multiple spark discharge” devices generate a bit more current flow, and induce multiple sparks (up to 3000-3,500 RPM, depending on model) to increase complete fuel burn, but typically beneficial only on power adder setups - forced induction or nitrous. The upgraded models - Digital 6, 7-series - add rev limiters, timing retard, two-steps, and programmable features required by high HP builds, or power adders. Putting a 7A on your engine will not change anything.
For what appears to be a stock engine with a CAI , headers and a catback, the stock ignition should be adequate. The 96/97 single-connector stock coil is supposedly superior to the 93-95 dual-connector coil.
The “multiple spark discharge” devices generate a bit more current flow, and induce multiple sparks (up to 3000-3,500 RPM, depending on model) to increase complete fuel burn, but typically beneficial only on power adder setups - forced induction or nitrous. The upgraded models - Digital 6, 7-series - add rev limiters, timing retard, two-steps, and programmable features required by high HP builds, or power adders. Putting a 7A on your engine will not change anything.
For what appears to be a stock engine with a CAI , headers and a catback, the stock ignition should be adequate. The 96/97 single-connector stock coil is supposedly superior to the 93-95 dual-connector coil.
02-05-2019, 11:35 PM
#4
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Re: Ignition boxes?
YOU DON'T NEED 57,000 VOLTS. Spray a 200-shot, or add 12# of boost, or open the plugs to 0.100, or run it lean, or bump the compression to 12:1. Probably still wouldn’t require 57,000 volts.
I explained it above.... the voltage is whaterever the laws of physics determine is required to jump the spark plug gap - width of gap, condition of electrodes, cylinder pressure, compression ratio, temperature of charge, A/F ratio, etc.. The voltage builds until the spark can jump the gap, and with a stockish engine, it's probably not more than 20,000 volts, if even that. And if somehow you built an engine that did require 57,000 volts, the 8.5mm plug wires would be inadequate.
Don't fall into the”bigger is always better” numbers trap.
I explained it above.... the voltage is whaterever the laws of physics determine is required to jump the spark plug gap - width of gap, condition of electrodes, cylinder pressure, compression ratio, temperature of charge, A/F ratio, etc.. The voltage builds until the spark can jump the gap, and with a stockish engine, it's probably not more than 20,000 volts, if even that. And if somehow you built an engine that did require 57,000 volts, the 8.5mm plug wires would be inadequate.
Don't fall into the”bigger is always better” numbers trap.
02-05-2019, 11:58 PM
#5
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Join Date: Nov 1998
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Re: Ignition boxes?
Point of reference..... here's the coil for an NHRA Top Fuel dragster. Max voltage is 45,000
https://www.holley.com/products/igni...SABEgKXT_D_BwE
https://www.holley.com/products/igni...SABEgKXT_D_BwE
02-06-2019, 08:21 AM
#6
Re: Ignition boxes?
I get what ur saying but i see ls3s and the new LT1s with very high voltage coils, i even saw an article where they got 10 hp from going from 45k volt to an 85k volt. All that extra fire has to be worth something i would think. I dunno im just weird, and love to experiment.
02-08-2019, 11:07 AM
#8
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Join Date: Mar 2013
Location: Petaluma, Ca
Posts: 155
Re: Ignition boxes?
Injuneer is right, once the spark begins the voltage won't go any higher even with a coil capable of very high voltages. On a test bench in air the spark should jump across the .050" gap of a stock spark plug at about 4,110 volts based on the dielectric strength of air (3,000 volts per millimeter). The presence of the fuel and the high pressure of the compression stroke increases this but not that much for a street engine. Once the spark starts the current will flow and there will be no further increase in coil or wire voltage as the current drains the energy from the coils magnetic field.
02-08-2019, 11:52 AM
#9
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Join Date: Aug 2005
Location: Las Vegas
Posts: 38
Re: Ignition boxes?
Yes, read from an author named Bell that greater than 50k volts is beyond the capabilities of available plug wires and will induce all kinds of misfires, crossfires and voltages in nearby wires - a bit of a tesla display.
But I do have reasons to like the analog MSD6AL since it gives me a kill wire/switch that I can hide/remote locate. And I like the "pill" used for rev limiter rather a tiny dial on other models - you never know when you need to let someone else have your car keys. Last feature is the multispark feature works in the RPM range of cruise for overdrive (but not all cars) and can only help fuel mileage.
What I'm saying is I don't see anything negative in using a MSD6AL and a few features I like. My 2 cents.
But I do have reasons to like the analog MSD6AL since it gives me a kill wire/switch that I can hide/remote locate. And I like the "pill" used for rev limiter rather a tiny dial on other models - you never know when you need to let someone else have your car keys. Last feature is the multispark feature works in the RPM range of cruise for overdrive (but not all cars) and can only help fuel mileage.
What I'm saying is I don't see anything negative in using a MSD6AL and a few features I like. My 2 cents.
02-14-2019, 08:34 AM
#10
Re: Ignition boxes?
Ill just get the 6a i mean its 10k more volts then im doing now, or 15, should make the difference. Other ignitions are very exspensive and could be spent on **** like a rear end lol.
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