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This is not news to a lot of people, but some still blindly recommend "performance" ignition parts. I've had the opportunity to do some in depth testing lately (through school) and totally confirmed that on modern ignition systems for 99.9% of vehicles, stock is as good as it needs to be and will provide all the spark duration your PCM is capable of dictating.
There's kind of a lot of interesting stuff I've learned in the last week, but as a comparison that people might remember, I had an MSD coil pack (made in China) and Ford Racing wires on my car. The car had no drivability issues and the components were less than 30K miles old. The plug ends of the wires looked pristine, but pulling the wires from the coil pack revealed that the coil pack terminals were completely corroded away, as were the plug wire terminals at that end. There was essentially at least a half inch air gap where there should have been a solid connection. The resistance in the wires and the coilpack were basically unreadable, far beyond spec. This still only stressed the coil pack to put out about 20K volts (verified on an automotive oscilloscope), and it was still probably capable of another 1/3rd of that before the spark jumped through the side of the coil pack or out a wire. There was relatively little spark duration due to the extra resistance, about 1.2 ms. It was only getting worse though and clearly needed fixing. I didn't pay for this expensive ignition stuff (previous owner, also way too found of orange interior bits), but one would think it would be at least as good as OEM for the price.
I bought a $17 set of Bosch plug wires that are surprisingly good, ranged in resistance from 400 to 950 ohms (very low), and a $40 coil pack from Airtex Wells, whoever the hell they are. It's from China also, but it tested out to right around 40K volts maximum output (wire briefly pulled from plug with no ground, 40K volts is not unordinary for a modern coil pack). The cars idle required about 15-18K volts, but anything much above idle the advance is more pronounced, compression pressures are less (easier to initiate spark), and the firing voltage dropped to probably 5-7K while spark duration increased to 1.5- 1.7 ms. The coil pack and wires are not SVT specific, the SVT has no special ignition components which should tell you something about how good ordinary stuff is these days.
My point is that my $57 set of coil pack and wires is doing everything that a fancy aftermarket setup could. It's all dictated by the PCM. My plugs are gapped relatively conservatively at .055", I wish I had taken the time to increase the gap incrementally to see how it affected firing voltage and spark duration at different RPMs. It might be that I could run a .070" gap or bigger with little decrease of duration, at the cost of a higher firing voltage and a little more stress on components.
So that's my rant, it's been really fascinating to do in depth testing and know without a doubt what an ignition system is capable of. You can visually inspect, you can ohm the primary and secondary sides of the coil pack, and you can buy an $8 adjustable spark tester that will stress your system to it's limits and tell you it's health.
There's kind of a lot of interesting stuff I've learned in the last week, but as a comparison that people might remember, I had an MSD coil pack (made in China) and Ford Racing wires on my car. The car had no drivability issues and the components were less than 30K miles old. The plug ends of the wires looked pristine, but pulling the wires from the coil pack revealed that the coil pack terminals were completely corroded away, as were the plug wire terminals at that end. There was essentially at least a half inch air gap where there should have been a solid connection. The resistance in the wires and the coilpack were basically unreadable, far beyond spec. This still only stressed the coil pack to put out about 20K volts (verified on an automotive oscilloscope), and it was still probably capable of another 1/3rd of that before the spark jumped through the side of the coil pack or out a wire. There was relatively little spark duration due to the extra resistance, about 1.2 ms. It was only getting worse though and clearly needed fixing. I didn't pay for this expensive ignition stuff (previous owner, also way too found of orange interior bits), but one would think it would be at least as good as OEM for the price.
I bought a $17 set of Bosch plug wires that are surprisingly good, ranged in resistance from 400 to 950 ohms (very low), and a $40 coil pack from Airtex Wells, whoever the hell they are. It's from China also, but it tested out to right around 40K volts maximum output (wire briefly pulled from plug with no ground, 40K volts is not unordinary for a modern coil pack). The cars idle required about 15-18K volts, but anything much above idle the advance is more pronounced, compression pressures are less (easier to initiate spark), and the firing voltage dropped to probably 5-7K while spark duration increased to 1.5- 1.7 ms. The coil pack and wires are not SVT specific, the SVT has no special ignition components which should tell you something about how good ordinary stuff is these days.
My point is that my $57 set of coil pack and wires is doing everything that a fancy aftermarket setup could. It's all dictated by the PCM. My plugs are gapped relatively conservatively at .055", I wish I had taken the time to increase the gap incrementally to see how it affected firing voltage and spark duration at different RPMs. It might be that I could run a .070" gap or bigger with little decrease of duration, at the cost of a higher firing voltage and a little more stress on components.
So that's my rant, it's been really fascinating to do in depth testing and know without a doubt what an ignition system is capable of. You can visually inspect, you can ohm the primary and secondary sides of the coil pack, and you can buy an $8 adjustable spark tester that will stress your system to it's limits and tell you it's health.
