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Discussion Starter #1
Have a Dominator EFI on a SBC with a FAST dual sync. The engine has a tough time starting when the distributor is phased correctly. Once the engine fires, it runs great. If I retard the distributor 15*, the engine fires right up. I've set the cranking timing to 1*, no change. Any suggestions?

Dave
 

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Is the ECU timing synchronized with the engine (timing light)?
 

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Is your "crank to run" rpm set higher than what the engine rolls over at? If not it is using the main timing table instead of the timing value in the cranking parameters.
 

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I'm not sure, but if this is the same gentleman that just called, he was trying to phase the timing with Idle Spark Control Active..... This must be disabled when phasing the ignition timing.
 

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Just to recap Synchronizing the EFI timing (laptop) with the engine timing (timing light):
Note: Use the software's "Enable Static Timing Set" (in the "Sync With ECU" drop down menu - Toolbar). Otherwise, you'll see the Idle Spark control timing fluctuate rapidly when using your timing light. I like to enter a static timing value of 30°.
1) The distributor is turned to synchronize the initial (idle) timing, then lock it down. Next, you need to ensure the ignition timing is synchronized across the entire RPM range.
2) Momentarily rev the engine and watch the timing advance with your timing light. It shouldn't move.
3) If timing advances or retards, adjust the "Inductive Delay" until the timing remains stationary.
Once the ignition timing is fully synchronized, the Timing Table can be tuned for each application.
Summary: The initial (idle) timing is synchronized by turning the distributor & locking it down; the timing at higher RPM is synchronized by adjusting the Inductive Delay in the EFI software. The first synchronization is physical, and the second synchronization is electronic. When finished, the timing as viewed on the laptop, should match what you see with the timing light, at all RPMs.
FYI: Just like a carbureted application, if your distributor ends up facing the "wrong" direction (aesthetics), you can remove the distributor assembly from the engine and reinstall it in the position you like without turning the inner shaft. You can remove the distributor cap and tape the rotor to the distributor body for maintaining alignment.

If you determine you need to fine tune the starting parameters:
Specifically, the Cranking Fuel and the IAC Parked Position; together these are the cranking air/fuel ratio.
Increasing the Cranking Fuel will usually start the engine faster.
Remember, if you're sequentially injected, the engine needs to "sync" (while cranking) before firing.
 

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Discussion Starter #8
Danny,
There's no inductive delay setting in the custom ignition type. The idle spark is also inactive. I have the crank to run set at 500rpm. Will a non dual sync distributor start the engine easier?
 

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Danny, there's no inductive delay setting in the custom ignition type.
There will be in the next update release (for some of the custom selections).

I have the crank to run set at 500rpm.
Why? What was wrong with the base map value of 400?

Will a non dual sync distributor start the engine easier?
Not unless there's something wrong with your existing cam sync distributor.

Once the engine fires, it runs great. If I retard the distributor 15*, the engine fires right up. I've set the cranking timing to 1*, no change. Any suggestions?
Just so I'm clear, if you physically turn the distributor to retard timing 15°, it starts better (1° Cranking Timing)?
But if you do the same thing software-wise (1° Cranking Timing), there's no change?
And you've confirmed (using timing light) that in both cases, the cranking advance was 1°?
 

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Discussion Starter #10
I might have figured it out. The module plate is in the 50* position. The distributor is set and sync per instructions. I set the config to 50* but couldn't get the distributor time and the engine had a hard start issue. I changed the the config to 1* and everything is doing what it's suppose to.
 

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Just so I'm clear, if you physically turn the distributor to retard timing 15°, it starts better (1° Cranking Timing)?
But if you do the same thing software-wise (1° Cranking Timing), there's no change?
And you've confirmed (using timing light) that in both cases, the cranking advance was 1°?
I might have figured it out. The module plate is in the 50* position. The distributor is set and sync per instructions. I set the config to 50* but couldn't get the distributor time and the engine had a hard start issue. I changed the the config to 1* and everything is doing what it's suppose to.
Yeah, something like that (distributor setup issue) is where I was headed. Good job.
 
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