Ignition Coil Comparison, Primary Energy
- Thread starter V8bait
- Start date
I heard you ran a 0.99 gap too or was that a 0.020? Wait, nobody knows what gap you ran yet as you haven't told us!
I heard you ran a 0.99 gap too or was that a 0.020? Wait, nobody knows what gap you ran yet as you haven't told us!
Sorry I tried a lot of plug and gap combinations with the coils. I tried copper plugs, Brisk silver and even tried those hand built GT-R plugs from Japan, misfire city btw. I found that .021 using the go-nogo method is what worked best on the N20 plug for me above 30psi. If I was running 28psi I would open that up to .025 and even bigger below that boost.
Bad choice for a comparison on the LS coils, assuming you used D585 coils. Those are commonly known to have problems at the dwell times you were testing them at. Try the other type of truck coil it's much better, I believe they are made by Metco. But even the standard LS 2/3/7/9 coils should do better in your test.
We tested the normal ones and they were less powerful. The issue you're talking about is when you dwell them too long and the smart coil triggers a protective spark, which is similar to advancing timing. This only happens at around 6ms, and yes it's a big problem... But only if you dwell them that long. Most LS builds will dwell them for around 4.5ms to avoid this. The 585 was the highest output LS tested.
In the .zip I posted there's some shots where we set the dwell to like 7ms and you can see the coil fire prematurely. Definitely shouldn't be called a "smart" coil lol.
Edit: @Milan here is a scope of the issue at long dwell on D858, purple is dwell signal, it's at ~7ms, you'll see the coil discharge on its own just before the signal ends. Big spark though.
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Tested them straight from the dealer, and yes the LS2 dwelled there fine without issues but was about half as powerful. IIRC, the LS2 coil also saturated before the LS truck coil did, so running it out past like 4ms didn't have any advantage anyway. I did not test aftermarket coils as there's too much variation, some are better some are worse. The D858 was just a lot stronger than the LS2 coil at any dwell, that's why we used it for comparison. But I'll try to find one of the others you're talking about.
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