Question about Spark Plugs
Melting Slicks
Joined: Mar 2007
Posts: 2,100
Likes: 12
From: Frederick Maryland
To start, I'd stick with the stock application...maybe open the gap from .035" to .045" since you'll have the HEI to fire it. Make sure it's properly tuned and timing is correct. Run it for awhile...maybe 500-1000 miles and the pull the plugs and see how they look. "Reading" plugs is somewhat of an art but it should tell you whether you have the correct heat range.
Do it regularly until you're comfortable you have it correct.
Do it regularly until you're comfortable you have it correct.
Team Owner
Joined: May 2001
Posts: 29,745
Likes: 3
From: Exiled to Richmond, VA - Finally sold my house in Murfreesboro, TN ?? Corner of "Bumf*&k and 'You've got a purdy mouth'."
CI 6-7-8 Veteran
CI-VIII Burnout Champ
St. Jude Donor '06-'10, '13
I agree. You can't go wrong with .045 on an HEI.
Pro
Joined: Dec 2006
Posts: 665
Likes: 0
From: wilmington nc
Running a smaller gap will produce a hotter spark, gap should be determined from the compression of the engine. Higher compression engines like smaller gaps with hotter spark. Changing the gap as little as .005 will result in a 80-100 degree temp change inside the cylinder. Were talking 450 degrees here, opening that gap up .010 will cool off cylinder temp considerable which in return will allow for carbon build up. It"s just a thought but you may want to research the compression of that 427 and gap acordingly.
Thread Starter
Drifting
Joined: May 2002
Posts: 1,546
Likes: 5
From: Sacramento California
Thanks for the replies, looks like I had better check the compression of the engine also. It was built when I bought the car and runs really well so I really haven't researched it's internals.
Race Director
Joined: Sep 1999
Posts: 11,360
Likes: 382
From: Plano TX
Running a smaller gap will produce a hotter spark, gap should be determined from the compression of the engine. Higher compression engines like smaller gaps with hotter spark. Changing the gap as little as .005 will result in a 80-100 degree temp change inside the cylinder. Were talking 450 degrees here, opening that gap up .010 will cool off cylinder temp considerable which in return will allow for carbon build up. It"s just a thought but you may want to research the compression of that 427 and gap acordingly.
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