finding power

[john h]

HI All,
I need to find power with Key on and Crank.  It cant be at the Ballast resistor because it needs 12V at all times during crank.  Any Ideas?

Thanks.
John

[drewcrane]

There is one spot on the starter relay ,that has 12 v when cranking ,I use it for my oil pressure switch for my electric fuel pump,use a meter to check it I think it is the post with the yellow wire.

[Chryco Psycho]

MOst ign systems like MSD & efi computers will use power from both of the wires at the ballst merged together ,, you can run a diode allowing only one way flow on the start wire if needed but I have never needed to .

[john h]

thanks for the replies.  THe EFI tech guys got back to me and said they have used the balast for this power at the 12v side.  I will have to get the meter out and see if thats the top or bottom and figure out the best way to tap that.  I'm planning on the upgrade to FITech EFI and I want to have all my issues and questions answered before the install day so it all goes smoothly.

Thanks.
John

[GoodysGotaCuda]

I used the ballast wireS to trigger my MSD. At the same time I got rid of needing to have the ballast due to an aftermarket coil didn't require cutting down the voltage.

[john h]

I used the ballast wireS to trigger my MSD. At the same time I got rid of needing to have the ballast due to an aftermarket coil didn't require cutting down the voltage.

is it true that the blue wire Ignition #1 has power at both run and start or do I really need to tap off the blue and the brown wire to achieve 12V at run and start. I will be keeping my Ballast and coil but allowing the EFI unit to act as my ECU.

Thank you
John

[Chryco Psycho]

The blue wire doesn't have power when ranking so it will not start , the brown wire only has power while cranking so both will need to be connected to the EFI the problem comes in that with them connected together you will have power back feeding to the coil & bypassing the ballast you will need to install a diode into the brown wire to allow power the EFI but prevent power going back to the ballast  otherwise the coil will fail prematurely

[dfrazz]

The blue wire doesn't have power when ranking so it will not start , the brown wire only has power while cranking so both will need to be connected to the EFI the problem comes in that with them connected together you will have power back feeding to the coil & bypassing the ballast you will need to install a diode into the brown wire to allow power the EFI but prevent power going back to the ballast  otherwise the coil will fail prematurely

I ended up tying the blue and brown wires together when I install the Firecore RTR distributor.

[john h]

I have attached the Fitech wiring diagram for use with timing control.  I was thinking the choke wire for the White wire in the diagram but do I power the coil with the brown and black tied together on the +side? NO ballast as I'm suing a blaster 2 coil that does not require lower voltage.