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Optimal timing for starting?

I have a msd 6530 and have been using 10deg advance to start and idle. Idle is good but starting has never been great. What is the optimal amount of advance for starting? Engine is standard 3.3L 7.5:1.
Thanks
Old 07-30-2014, 07:25 AM
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Around 0 (TDC) to 2 BTDC. Too much advance and the combustion pressure works against the starter.

I also idle at 10. It definitely seems like the magic number for the old flat six. I can also start OK with 10, used it for a couple years, so double check your fuel system.
Old 07-30-2014, 09:20 AM
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I use 10 degrees no problem. Fires right up, with 16-18 at idle.
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Old 07-30-2014, 04:58 PM
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I think fuel mixture is more important for starting than advance. My 930 fires after about 1 second of cranking. I'm at 14 degrees BTDC until 1200 rpm when it starts to ramp up. My CP is 1.4 bar at 75F. My cold start injector is disconnected. Check your fuel and richen it up a bit when cold.
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Old 07-30-2014, 08:35 PM
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Ok, so I played around with different timing settings for start and idle.
Start take a long time as I need to leave the car long enough to retest for cold start. It's definitely better with the cold start disconnected.
It turns over better at a low timing mark like 4deg. But always the same long start regardless of the setting.
I was making changes to the program today while in the car and then tried to start and it did but idle was super low. I then realized that the WUR had warmed up by that time so the car starts great on a warm CP but then immediately needs the cold CP to hold idle and warm up.
This means my cold CP is too low for good starting but is perfect for holding idle?
How is this possible?
Don't you need more fuel to start and not less..
Old 08-04-2014, 07:45 AM
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