if you don't have the original ECU for an FJ, what type of modifications do you have to do to the stock distributor if your running a stand alone, like a megasquirt? any mods necessary or is it okay to just hook up like an MSD6AL and it'll work fine, as far as advance is concerned.

The CAS in the distributor has NO influence on ignition advance.
That is controlled by the ECU
The FJ20 CAS is an optical interrupter type and will work on Megasquirt ECU's as well as a zillion others.
The setup is available in the megasquirt documentation.

L8tr
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