Problem with HEI Coil
Thread Starter
Safety Car
Joined: Oct 1999
Posts: 4,403
Likes: 1,276
From: Florida
Problem with HEI Coil
I added an Accel Brutethunder coil to my stock hei coil (Lars rebuild and fine tune)...I put the distributor in with new Accel cap and rotor set, installed new spark plub wires...but did not put on the new coil cover just then as I did not have a black cover (got it today)...when I started up the car to time it (as per Lars instructions), I notice that there were mini sparks coming from the black ground wire feral attached to one of the 4 coil attaching screws...is this normal?
Race Director
Joined: Sep 2001
Posts: 10,560
Likes: 439
From: Wellington, FL
St. Jude Donor '11 thru '25
I can't imagine anything in a car that generates sparks in an open environment would be normal. While I could be wrong, if I'm understanding what you are describing, I'd say it is a dangerous situation and that the car should not be driven until repaired. Perhaps you can contact Lars. 
Burning Brakes
Joined: Apr 2004
Posts: 847
Likes: 0
From: Des Allemands LA
I added an Accel Brutethunder coil to my stock hei coil (Lars rebuild and fine tune)...I put the distributor in with new Accel cap and rotor set, installed new spark plub wires...but did not put on the new coil cover just then as I did not have a black cover (got it today)...when I started up the car to time it (as per Lars instructions), I notice that there were mini sparks coming from the black ground wire feral attached to one of the 4 coil attaching screws...is this normal?
Thread Starter
Safety Car
Joined: Oct 1999
Posts: 4,403
Likes: 1,276
From: Florida
the connection was clean. and tight..all new parts...grease on both sides of the rubber insulator ring between the new coil and new cap...got a reply from Lars (great guy)...got feed up...so installed the 29 year old coil...no sparks...returning new hp coil tomorrow...end of story...thanks bunches
Race Director
Joined: Sep 2001
Posts: 10,560
Likes: 439
From: Wellington, FL
St. Jude Donor '11 thru '25
the connection was clean. and tight..all new parts...grease on both sides of the rubber insulator ring between the new coil and new cap...got a reply from Lars (great guy)...got feed up...so installed the 29 year old coil...no sparks...returning new hp coil tomorrow...end of story...thanks bunches
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Racer
Joined: Apr 2005
Posts: 464
Likes: 0
From: Charleston South Carolina
I had this problem too with all kinds of replacement parts to my HEI new cap, rotor, coil, wires and finally a new distributor. I was figuring on a miss so I got one of those clear caps that you can see the individual sparks inside and I was amazed at the inconsistancy. I went to a separate coil style MSD distributor and problem solved. Most will say the Hei is good enough but not for me after what I saw, even with EVERYTHING replaced. I have a more "racer" style setup and I'm not using any mech advance or vac advance, it's locked out at 36 with an MSD digital 7 box using the 20 deg. start retard feature with great results.
The main reason I went this route was because with the old setup I couldn't get a steady reading with the timing light no matter what I did.
The main reason I went this route was because with the old setup I couldn't get a steady reading with the timing light no matter what I did.
