plug gap setting on 390 hybrid
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Joined: May 2004
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From: Colorado
plug gap setting on 390 hybrid
Have a 75 f-100 project truck. Motor is a 390 4V from a 68 ford galaxy. Came with point disributor. Changed the plugs today with Autolight 45's. Set the gap at .035. Went to the distro to change points. The distro looks like a point distro. I was just hoping it wasn't a dual point. It has a red cap. Imagine my suprise when I took off the cap, and saw a point distro rotor cap, with no points! I think its electronic? Now my question is do I set the gap on the plugs at .035 or .045? It runs great at .035, but I want it set right. I acn adjust from there. This truck has been rigged like you wouldn't believe.
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Joined: Jan 2001
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From: Virginia
.035 will be fine. If you have some sort of hotrod high-output ignition box, you can set them wider. A higher voltage system will jump a wider gap.
The deal is, the wider the gap, the more power you can get. But if you run the wider gap with a regular ignition, the plugs will have to be changed very often. They will wear a little bit, and the regular ignition won't be able to jump the wider gap. The higher output ignition will jump the wider gap, but there is still a limit to it's ability.
The gap is a compromise. Longevity versus performance. If you want the plugs to last a long time, leave the gap smaller. If want to change them more often, then widen the gap a little for some increase in power.
The deal is, the wider the gap, the more power you can get. But if you run the wider gap with a regular ignition, the plugs will have to be changed very often. They will wear a little bit, and the regular ignition won't be able to jump the wider gap. The higher output ignition will jump the wider gap, but there is still a limit to it's ability.
The gap is a compromise. Longevity versus performance. If you want the plugs to last a long time, leave the gap smaller. If want to change them more often, then widen the gap a little for some increase in power.
