Ignition base timing JDM EDM CA18DET

Nistune topics specific to the 6802 cpu

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MechanisSan
 

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Ignition base timing JDM EDM CA18DET

Post by MechanisSan »

Hi folks
Officially the JDM ECU demands the base ignition timing to be set at 10° and with the EDM ECU it needs to be set at 15°, for whatever reason.
I have an EDM CA18DET with an EDM ECU that I have loaded the JDM base image on because I need the butterfly switching option (that actually does work).
The actual ROM with all the mapping is still the same one that I had on it before I changed to the JDM base image. Now I did check my base ignition timing with the timing light like I have done many times before, and I saw that it is at 10° unlike 15° what I always adjusted it to. The CAS is still in the same position like when it was at 15°. Because I've made some changes to the engine I thought it might has changes that, so I went and adjusted it to 15°. But when I was acceleration during the test drive I could clearly hear ugly detonation at around 4000 rpm. Of course I instantly stepped of the throttle. Before the point where the knocking occurred it also had noticeably more grunt.
Now I am confused. Before I've adjusted the base timing it never knocked, so I am certain that it came from that.
Does the base image define if it needs 10° or 15° base ignition? I would have thought that is defined by the maps in the ROM!?
Matt
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Re: Ignition base timing JDM EDM CA18DET

Post by Matt »

Should be the idle/decel timing maps in the ECU

One thing you could check was the previous base timing (reported by consult) from an older log, and your current reported consult timing. If earlier one was 10 and current one 15 then the timing increase moved with the JDM image (and tune)

The consult reported timing should match that shown on your timing light
MechanisSan
 

Posts: 18
Joined: Wed Mar 25, 2015 7:56 pm
Location: Europe

Re: Ignition base timing JDM EDM CA18DET

Post by MechanisSan »

Alright thx. I'll check that
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