Spark dwell settings

[Mstansbury0704]

Have a 2000 procharged ws6 with an ls1 and factory ECM. coils needed replaced so I purchased a set of D585 coils. My question is how do I adjust my dwell timing to ensure I stay below the dreaded auto fire? I have a couple multiplier tables in my pcm that I?m unsure about how they work. Do they both apply to the main table or just one etc?. If someone can help me or provide a link to their tune using D585s I can look at I would greatly appreciate it. This is important to me, I?ll gladly buy someone a case of beer over PayPal for helping me.

[2xLS1]

What vehicle were those coils used on?

[kevin87turbot]

What vehicle were those coils used on?

A lot of the mid 2000's applications used them. From memory, all of flex fuel applications used them. The 2003 Tahoe file that I've attached had them on it.
2003tahoe53Lbenchtunerussellstock.hpt

[anniversaryss]

I would use the dwell settings form whatever vehicle uses the d585 coils (usually the trucks).

If you look at the dwell + multipler on fbody pcms they are well above 5ms and then some. That's my opinion.

[Mstansbury0704]

Yes that was my thoughts, copy the main table and all of the multipliers over and then maybe take a percent or two out of them to be safe. Also, would I copy the power up initial settings and all as well? If this doesn’t work I’ll be posting again for tuning help lol. Hoping either my 23 yr old ls1 coils have just had enough. Around 2-3000rpm around 95-100kpa I get misfires(procharged car and big cam) so very light throttle to be at 100kpa. Just enough to maintain speed and rpm. Tried everything tune wise. Put it into PE with no luck and then tried stoich, pushed timing up and down by 4 degrees. No difference. It has those shitty msd wires. Hoping going with a working set of coils and some fire cores wires will at least assure me it’s not ignition related, I don’t have much hope, but it’s lighting off a good bit of water/meth and high compression so it couldn’t hurt to get some hotter coils anyway. Also, I wonder why GM opted for more aggressive main dwell times with the truck coils then took it all away with the etc multiplier

[anniversaryss]

Yes that was my thoughts, copy the main table and all of the multipliers over and then maybe take a percent or two out of them to be safe. Also, would I copy the power up initial settings and all as well? If this doesn’t work I’ll be posting again for tuning help lol. Hoping either my 23 yr old ls1 coils have just had enough. Around 2-3000rpm around 95-100kpa I get misfires(procharged car and big cam) so very light throttle to be at 100kpa. Just enough to maintain speed and rpm. Tried everything tune wise. Put it into PE with no luck and then tried stoich, pushed timing up and down by 4 degrees. No difference. It has those shitty msd wires. Hoping going with a working set of coils and some fire cores wires will at least assure me it’s not ignition related, I don’t have much hope, but it’s lighting off a good bit of water/meth and high compression so it couldn’t hurt to get some hotter coils anyway. Also, I wonder why GM opted for more aggressive main dwell times with the truck coils then took it all away with the etc multiplier

GM does some crazy stuff. Iirc the truck settings will put your dwell in the low to mid 3ms range. It should be fine. I would personally swapped over all settings