I'm getting some misfire at around 8-9k and then a lot past 9k. you can see a little dip on power at around 8700, some misfire there, then after 9k, a lot of misfire. i let off before before hitting rev limit at 9300 because of so much misfire. the check engine light is not blinking from misfire (which it has before at lower rpm during cruising, but went away when i replaced MAF sensor).
New ported engine
AC Delco D585
Bennett Built LS coil harness and MSD 8.5mm plug wire.
Versatuner
Last edited by trackjunkie; 10-10-2018 at 08:13 AM.
Just thoughts that you may have already addressed but didn't mention...
Have you tested the coils with an HEI tester? The D585s are supposed to be more robust but that doesn't eliminate the possibility of one or more going bad.
Also, have you altered the coil dwell settings? All else being equal, D585 coils need a longer dwell than OEM.
all components are new. did not test coils with HEI tester. did not change dwell settings. wasn't sure what these numbers represent in the dwell table.
Last edited by trackjunkie; 10-10-2018 at 08:45 AM.
Did you fix? i still get occasional, intermittent power loss, stumbles, surges... i am thinking ESS, MAP/Baro sensor, or the ignition condenser. my coils, wires, plugs, MAF all new, injectors flow tested, new fuel pump, pulls great... most of the time! dang intermittent issues...
i dont get misfire/CEL anymore while driving on street after replacing the MAF sensor, but did get a big stumble, feels like a complete engine shut down for like a split second. that used to happen more often before replacing the MAF, even when on track. After replacing the MAF, it only happened once on street.
on track, i was still getting CEL blink during light throttle at the last track event.
since switching to e85, i didnt get misfire near redline like i did before on 93 pump gas while on the dyno. so i'm hoping there wont be misfire on track at the next event. when it misfire on the dyno before, i can hear it but no CEL blinking.
Last edited by trackjunkie; 11-02-2018 at 10:25 AM.
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