krayneeum wrote:
bountyhunter wrote:
krayneeum wrote: It really is insane how much of a difference it made-- so much more power!!! ..
Then I would suspect the coil is bad.
Well these are 1 year old coils, but that's not out of the question I guess. But really I measured a clear voltage loss through the harness before the mod. Coils are simply now getting proper voltage-- that would account for more power, don't ya think?
No. Any decent coil should be able to put out sufficient spark even with a pretty low voltage, I would guess as low as maybe 8V should still be plenty. The thing about spark is this: they design in extra, and you only need enough to light the mix. Extra doesn't do anything more. Although a very weak spark can cause bad running, once you get it up far enough going higher doesn't increase power. I suspect a voltage starved coil would show diminished abilities at highest RPM's but I think the voltage would have to be pretty low.
Remember that under starting (cold crank) your battery voltage can drop as low as about 8V and the designers also allow some voltage losses in switches and harness connectors so that coil has to be designed to fire your engine with as low as about 5V driving the POS terminal. We designed IC's and systems for automotive and they all had to be certified for full performance down to 5V because of cold crank requirement. When the engine fires, your system voltage will come up to about 14V as it raises the battery voltage up. At that point you should have AT LEAST 10V or more on that coil unless there is something seriously wrong with your ignition switch or harness connectors.
What voltage was at the coil terminal?
