Mystery timing?
Thread Starter
TECH Apprentice
Joined: Jun 2012
Posts: 372
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From: Mississauga Ontario Canada
Mystery timing? has anyone seen this mystery timing while datalogging?
I set my main spark tables for 30* advance @ WOT and it targets 34-36* in the areas I clearly set lower and it causes a bit of knock retard.
It was really bad before I tuned it, I've eliminated most of the knock retard though.
Anyone know why? should I just factor this extra timing into my tune and drop the main tables down a few degrees to compensate?
thanks!
I set my main spark tables for 30* advance @ WOT and it targets 34-36* in the areas I clearly set lower and it causes a bit of knock retard.
It was really bad before I tuned it, I've eliminated most of the knock retard though.
Anyone know why? should I just factor this extra timing into my tune and drop the main tables down a few degrees to compensate?
thanks!
pretty common knowledge that the pcm adds a few degrees to what you program. Mine is programmed to 29degrees in tunercat.
I see MSD opti in your sig though and maybe the timing adjustment thing on it is advancing the timing. Only way to know is keyed hub, timing pointer and timing mark of some sort be it timing tape, degreed damper or just a single mark and a dialback light.
I see MSD opti in your sig though and maybe the timing adjustment thing on it is advancing the timing. Only way to know is keyed hub, timing pointer and timing mark of some sort be it timing tape, degreed damper or just a single mark and a dialback light.
Thread Starter
TECH Apprentice
Joined: Jun 2012
Posts: 372
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From: Mississauga Ontario Canada
Yah ok that's what I thought. If its common knowledge then it's odd how hard to find literature on it.
Yah I have an MSD opti but I set the timing to 0 advance/retard when I installed it. Good to know other people are running around the same timing as me though!
Yah I have an MSD opti but I set the timing to 0 advance/retard when I installed it. Good to know other people are running around the same timing as me though!
If you are getting retard with the setup in your sig at 30 programmed IMO there is something going on, be it lean or the MSD not truly "zero". The only way to know is the keyed hub and all.
I had mine at 30 degrees programmed for awhile an settled on 29 because it went faster not because it was knocking. I run a lot more compression than your sig would suggest you are.
I had mine at 30 degrees programmed for awhile an settled on 29 because it went faster not because it was knocking. I run a lot more compression than your sig would suggest you are.
Thread Starter
TECH Apprentice
Joined: Jun 2012
Posts: 372
Likes: 0
From: Mississauga Ontario Canada
yah fair enough i have stock heads and everything else. maybe it is the optispark, but I set the way the instruction said to do it, it was a long time ago though. the weird thing is wouldent that effect the timing at every RPM? when I am cruiseing/part throttle it seems to be right around the targeted advance. just in PE mode. oh well I'm going to play around with lowering it a little in the tune and taking the datalogged number as fact. I am going to buy a wideband soon, so Ill know if I'm lean.
yah fair enough i have stock heads and everything else. maybe it is the optispark, but I set the way the instruction said to do it, it was a long time ago though. the weird thing is wouldent that effect the timing at every RPM? when I am cruiseing/part throttle it seems to be right around the targeted advance. just in PE mode. oh well I'm going to play around with lowering it a little in the tune and taking the datalogged number as fact. I am going to buy a wideband soon, so Ill know if I'm lean.
