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Hooking Up A Lucas Sport Coil

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kyreb1862

kyreb1862

Jedi Knight
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OK, I recently posted about installing the new Lucas coil on my 77 MGB. At the time everyone agreed that I needed to bypass the resistance wire to my coil to get the full benefit of the coil. The problem is my car is not hooked up like the drawings. My car was retrofitted with the CEI ignition system. Instead of the 2 white and light green wires shown in the drawing I have 2 white wires. One white wire goes from the coil to the CEI unit, the other white wire is the hot line. I checked this line with the meter and it shows a full 12 volts. Is this correct? How could I tell if this is a resistance wire?
Input please my friends.
 
The bentley shows a white wire going to the drive resistor. Is this the white wire that is now hooked to the + side of the coil. If so, does it have a resistance section in it. The only resistance wire shown in the bentley is on the green and white wire. On my car the induction heater is no longer used. Could the green wire that formerly powered it be used to connect to the coil if it turns out that the white wire connected to the coil does indeed have a resistance section in it?
 
John, I think you'll find the white wire is just that: a wire. If you use it for the coil feed and (by implication) you're now using points, the ground side to the dizzy. It should be fine.
 
Hi John, How was the original coil connected in the circuit. Measure the resistance of the old coil. If it measures ~ 3 0ms. No resistance wire was used in the car. Now simply hook the the Lucas sport up just like the original coil was connected and you are good to go.--Fwiw--Keoke
 
kyreb1862 said:
actually I'm using the CEI ignition system.
Click to expand...

The CEI and Opus systems had the ballast resistor built into the harness. Refer to the stock schematics at https://www.advanceautowire.com/mgb.pdf

That said, it sounds like your wiring was not done to factory spec. If you're getting the full 12v from the hot side. I've measured the voltage on my stock wiring and found that I'm getting 6v and I do have the CEI setup with the two white/lt green plus the wire from the CEI unit.

Hope that helps.
 
fleshy1 said:
kyreb1862 said:
actually I'm using the CEI ignition system.
Click to expand...

The CEI and Opus systems had the ballast resistor built into the harness. Refer to the stock schematics at https://www.advanceautowire.com/mgb.pdf

That said, it sounds like your wiring was not done to factory spec. If you're getting the full 12v from the hot side. I've measured the voltage on my stock wiring and found that I'm getting 6v and I do have the CEI setup with the two white/lt green plus the wire from the CEI unit.

Hope that helps.
Click to expand...

Thanks for the reply. My coil is hooked up in the following way: On the + side are two white wires. One goes into the CEI unit the other is the hot lead. The hot lead shows 12+ volts on my meter. On the - side are two white with black stripe wires and one green with a yellow stripe wire. All the wiring has factory connections. I am not sure what the green with yellow stripe wire is for. Anyone else know?
 
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