GM HEI in a 74 question ???
Thread Starter
Drifting
Joined: May 2005
Posts: 1,909
Likes: 6
From: Lake Arrowhead - Georgia > 72 Base Coupe & 74 BB Roadster
GM HEI in a 74 question ???
I have just switched from the original points TO a GM HEI distributor in my 74 model 454.
Do I leave the (74) R44T spark plugs and gap setting?
OR switch to ________ plugs and gap them at _______ ?
Thanks...............
Do I leave the (74) R44T spark plugs and gap setting?
OR switch to ________ plugs and gap them at _______ ?
Thanks...............
Drifting
Joined: Jan 2006
Posts: 1,944
Likes: 22
From: Yooperville MI
Fred, Your gap width is determined by the ignition coil you are using. If you are using a stock coil, gap the plugs at .035". Higher output coils will allow you to open the gap wider. However, a wider gap with a stock coil will put more load on the coil and most likely shorten the coil life since the coil needs to work harder to jump the wider gap.
Being able to run a larger gap will improve combustion.
Being able to run a larger gap will improve combustion.
Le Mans Master
Joined: Sep 2001
Posts: 7,739
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From: Unreconstructed, South Carolina
