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Big Block Chevy MSD locked Distributor Trigger setup


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Have to install a Atom G4+ Ecu on a Big Block Chevy with MSD locked Distributor, reluctor Trigger inside Distributor.
What is the correct Trigger setup to avoid kick back at starting and to have correct rotor phasing?
Do i have to use an adjustable MSD Rotor?

Thank you

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You will have to run tooth per TDC mode with no sync.

Trigger points will need to be close to tdc 0-10btdc

Rotor will need to be close to a tower too at this point.



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To add a little more info to Simon's response;

I've only ever set up one V8 with a MSD distributor and its rotor to reluctor phasing was perfect for the 1 tooth per TDC mode without any "adjustable rotor" needed.  Basically what this trigger mode does is during cranking (RPM<400) the ECU does not attempt to do any timing control at all - it just fires a spark at the instant it sees a tooth so this makes cranking timing very stable as the ecu does not need to predict advance when crankshaft speed is erratic.  It does mean however that the teeth need to occur at a suitable position for cranking timing - as Simon says 0-10deg BTDC would be good for most engines.

So to set this up, manually turn the motor so it is resting at about 10deg BTDC #1.  Rotate the distributor body so that one of the reluctor teeth is perfectly centred under the sensor.  Now look at the cap post position in relation to the rotor and the rotor should be just "leaving" the post.  If the rotor is not in the right position then you will have to change the phasing somehow.  Sometimes that may be an adjustable rotor, move the sensor, or file a new "key" to locate the cap.



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