Switched 12v that wont loose power between IGN and crank

Knebel

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Hey.

I have to rewire some of my EFI stuff... I've been chasing this issue for quite a while. Little story upfront, my EFI requires a switched 12v source that stays active during crank and run. I deleted the ballast, combined the wires and am triggering a relay that gives power to said switched 12v efi wire and ign coil +.

The problem I have is, that this sytem looses power for a brief moment when the key is let go from crank and switches into run. That results in a tailchasing start/stall with the EFI and ign coil briefly loosing power.

Is there another wire/ switched 12V source that will be on in both crank and the run position, thats not switched between crank and run?
 
Hey.

I have to rewire some of my EFI stuff... I've been chasing this issue for quite a while. Little story upfront, my EFI requires a switched 12v source that stays active during crank and run. I deleted the ballast, combined the wires and am triggering a relay that gives power to said switched 12v efi wire and ign coil +.

The problem I have is, that this sytem looses power for a brief moment when the key is let go from crank and switches into run. That results in a tailchasing start/stall with the EFI and ign coil briefly loosing power.

Is there another wire/ switched 12V source that will be on in both crank and the run position, thats not switched between crank and run?
I am thinking of an accessory feed by the fusebox. You would have to double check this with your multi-meter.
 
from wht I just studied - the sniper and pertronix both have this issue. solution was relay driven off back of IGN switch, or the one I liked, was +85/6 wire trigger wire to +coil.

that may be the ticket.

try not to die -

- saylor
 
You MIGHT try a momentary contact button going to a relay, eliminating the 2nd position on the ignition key/switch altogether. This way, you can supply steady power to your EFI system, and engage the starter when you need to. The better you isolate the power to the EFI from the starter, the better it will start.

Put the main ignition circuits on a good, high current relay which will engage from the key in the 1st position. Feed your momentary contact button directly from the battery + terminal, using a fusible link for overcurrent protection. THAT should suffice for your fussy EFI and supply good starting current to the starter.

My own approach would be probably to take an ax to the EFI, but I realize it is a more efficient way to manage an engine, and some folks will prefer it. You can test my suggestion easily enough by using a diagnostic starter switch hooked to the relay right on your firewall, by the master cylinder, if you still have that.....

Good luck!
 
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