Best coils for boosted Ls?
D585's (and these are the "high output" FireCore versions)
D581 Pretty big difference!
I have to say, if I would have done that test like that, I’d have got zapped!
Why are you guys running a projected tip heat range 8 plug at that power level? That's probably part of your gap issue, 1200whp or 30-32PSI barely puts a heat mark on a 7 heat range non projected tip like the 3346/BR7EF and it stays happy to 37+psi even with 200+ IAT's.
Here is a new 8 on 15ishlbs and 17*. Maybe its just too much timing...
Here is a new 8 on 15ishlbs and 17*. Maybe its just too much timing...
Yours looks more like the NGK R5671-8 with a gasket seat: NGK.com: R5671A-8 NGK 4554 Racing Spark Plug
Your plug still looks a little soft to me. Do you mean wanting a hotter plug? I guess not if you are going to turn up the boost, those plugs are good for more like 40 psi
Yours looks more like the NGK R5671-8 with a gasket seat: NGK.com: R5671A-8 NGK 4554 Racing Spark Plug
Your plug still looks a little soft to me. Do you mean wanting a hotter plug? I guess not if you are going to turn up the boost, those plugs are good for more like 40 psi


Dang it man U gotta quit talk'n! Now you got me thinking I Sync'd the timing wrong and I've got alot more lead in it than my IGN map says... Once it's in the bend I usually stop. Don't want to push the tune up hard at all. What do one of your non-intercooled 7's look like after a pass with decent boost in them?
Last edited by Forcefed86; Jul 26, 2022 at 03:00 PM.
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Dang it man U gotta quit talk'n! Now you got me thinking I Sync'd the timing wrong and I've got alot more lead in it than my IGN map says... Once it's in the bend I usually stop. Don't want to push the tune up hard at all. What do one of your non-intercooled 7's look like after a pass with decent boost in them?
Across the board, from 99kpa to 350kpa?
Found this on the DIY Autotune site.
From this data, the D585 looks better than the D581. So interesting the spark jump test RX7 did showed different.
Or maybe I’m missing something?
At any rate, the IGN-1A is vastly superior. But very cost prohibitive for my budget.
I agree, be curious how much its actually worth on a "normal" setup with a functioning OEM coil pack vs the fancy ones. Most guys with the fancy stuff are on big power methanol setups where an OEM coil is not optimal.
D581's on this setup w methanol on 41lbs. 5.3 107mm (not an SBE and heads had work). Reportedly went quicker, but saw it did a 4.50 at ls fest before it crashed.
Hellbesnts10 also went 6.80@209 on D581's on M1.
Last edited by Forcefed86; Jul 28, 2022 at 11:38 AM.











