Written by bille
How to trigger an aftermarket ignition for a 4 cyl internal coiled Fronty:
Tools/Materials
Rotozip or Dremel
Drill press
cheap handheld grinder (metal and diamond blades)
Good solid metal electrode spark plugs
4 banger ignition cap
100% clear silicone (aquarium glue)
It isn't that much hassle w/ the right tools and components. I have a 98 fronty (w/stock internal coil dist) and have installed a Jacob's Mileage Master ignition - all you have to do is - get another cap to practice on, and (looking at the outside of the dist cap)- there's a ridge on the top (goes from center of cap to perimeter). That's where the coil is passing it's juice to the rotor. If you put a couple of terminals (made out of a spark plug) near each end of this ridge, then on the inside, cut into the conductor and break the circuit(rotozip comes in handy), you have effectively bypassed (to the outside) your coil signal that you need to trigger your new ignition. So you can now run plug wires from this to your aftermarket ign, and then back to the dist.
The internal cut needs to have ~1/2" of the conductor length cut out. I always opt for overkill. Maybe less is ok.
The rotozip kinda smears the plastic and conductor together, so you have to hit it in stages and periodically clean. AND MOST IMPORTANT!> mask off everything inside - except where you cut - before you start grindin. Makes the cleanup much easier. You don't want powdered aluminum from the conductor spattered all over the inside. The cut away conductor on the inside can be filled up w/ clear 100% silicone.
Adding the terminals is a bit trickier: Use the metal blade to cut through the metal portion of a sparkplug. You basicailly want to strip it down to just the terminal end, insulator shell, and about 3/4" of electrode sticking out the bottom. That will give you enough for later final cut to length- The diamond blade is for the insulator portion (metal blade wont touch it). Get rid of the metal hex part and the ceramic around the electrode at the sparking end. Use an 8-32 tap to thread the electrode and drill (2) holes (little smaller than the tap size) near each end of the ridge on the distributor cap. These will be for the electrodes you made. When you're drilling you can feel the difference as the drill goes thru the plastic, then hits the internal conductor, then passes through that into the plastic again. Stop there! You just want to go thru to the conductor and stop just past it. You don't want to drill all the way through.Use the male 8-32 tap to thread the holes. Thread on the sparkplug "coil terminals" after cutting them to proper length.
Attach your new terminal wires, and you should be free to proceed w/ your install. Should your aftermarket ign ever fail ,you can always use one of the terminal wires to jumper the (2) "coil terminals" together. Now you're back to your stock internal ignition coil used as backup.
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