I'm a ford guy trying to help a buddy with his chevy crate engine install. It's a 502 Goodwrench engine, has the dist. and wires already on it ect. Can I just run a 12 volt thats hot from the key to the dizzy? Thats what I did and it keeps fouling plugs like the spark isn't hot enough. Any advice? Thanks in advance.
does it foul plugs like the carb is adjusted wrong? what size wire did you use, if it's HEI then you need a fat power wire for it, 12 gage would be good.
As I remember it, the HEI has an internal current limiter that maxes out at 5.5 amps. It's all automatic so you don't need any ballast resistor. There was a very cool SAE paper from the mid 1970s by Huntzinger that describes how it works inside. EDIT: Here is a like to the abstract of the paper -- http://papers.sae.org/750346... (and fixed the spelling)
We changed carbs and the problem is still there. It does have a small wire,maybe 14g. I'm going to try the fatter wire and see what that does. The car had a MSD system and we removed all of that and just moved the 12v with the key wire to the factory dist. Maybe I need to check that wire for voltage? Thanks for all the help.
Make sure that you are providing power to the correct pin on the HEI. There are four, as I recall: Coil -, unused, tach, and B+. You need to connect +12v to the B+ pin.
Thanks for all the help guys. I think I got it figured out. Ran a bigger power wire and while doing that noticed my friend had tapped in to the wire to power up his electric choke. We were getting 11 volts until I noticed that and now have 13 volts to the dist. Seems o.k. now. Thanks for the shop lesson! Never to old to learn. Tom.
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