coil question
Thread Starter
Drifting
Joined: Jan 2006
Posts: 1,554
Likes: 3
From: pasadena in the great state of TEXAS
St. Jude Donor '09-'10-'11-'12-'13-'14-'15-'16-'17
coil question
hi all, i have a 1978 l-82 that has 25500 mikes on it, i changed the plugs the other day during a header install. my question is does the coil need to be replaced due to it's age? i am getting ready to change the cap and rotor and didn't know if the coil could get weak with age. the car runs fine so i thought i would get some advice... 
Racer
Joined: Sep 2007
Posts: 286
Likes: 0
From: Pensacola Fla
coil
The old addage applies,if it ain't broke don't mess with it,carry a spare!Kidding aside I would leave it alone unless you are upgrading your ignition system to get better performance and the major suppliers all have decent ignition kits you can install. 
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
If the top cap is not cracked and leaking off its charge, it should be fine. You can check resistance of the primary and secondary coils, but that really doesn't test the unit for integrity at full voltage on the secondary side.
Le Mans Master
Joined: Mar 2001
Posts: 6,640
Likes: 287
From: Ann Arbor Michigan
A lot of the aftermarket coils are cheap copies of the original GM HEI coil. So you might be better off keeping your original. But, if it were me, I'd buy a new GM coil since yours is 30 years old.
Safety Car
Joined: Aug 2001
Posts: 4,883
Likes: 11
From: North Easton Mass
If the engine is running OK you probably don't need to replace the coil. If the coil is in good shape cosmetically it might be worth storing it and putting in a new one if you are interested in NCRS-type judging at some point. I'm assuming you have the HEI ignition so there should be plenty of voltage to the plugs even if the coil is a little weak. Older points-style coils only put out 15-20K volts so when they got weak or developed some other ignition problem it was much more noticeable.
Rick B.
Rick B.
