Plug Gap ???
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Joined: Aug 2001
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From: Ansonia CT
Plug Gap ???
I have an approx 300 HP 350 crate motor with 79 block, 86 vortec heads, cross wind manifold with Edelbrock 600 cfm on it, headers mild comp cam. I need to change the plugs and am going with the Accel shorty plugs # 576S . they are gapped at .035" , should I leave them there, or open them up to say .040 or 042. Any suggestions would be appreciated. Thanks ( Save the Wave!!! ) Happy Holidays to ALL!!!
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From: Ansonia CT
Originally Posted by comp
stock ign. i go .035 ,,,.045 is max i use with aftermarket
Burning Brakes
Joined: Apr 2004
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From: Des Allemands LA
You can run .045 with that setup and not have any problems. However the smaller the gap you run and still have proper burn, the easier you are on the rest of the ignition system (i.e. coil and wires). Start @ .035 if the plug reads are good and there are no issues with the motor (which there shouldn't be if everything else is tuned right) you will be fine.
ltlevil
ltlevil
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Joined: Aug 2001
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From: Ansonia CT
Originally Posted by BigBlockk
What is so special about this engine that plug gap would be so critical?
BigBlockk
Later.....
BigBlockk
Later.....
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Racer
Joined: May 2000
Posts: 386
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From: Niedernhausen, Germany
Gap
If you have an HEI, I would run it with at least 0,045. Otherwise, where would the benefit be of the High Energy Ignition, i.e. the higher voltage these systems put out in comparison to old breaker type distributors?
The larger spark helps starting, economy and power.
Regards,
Thomas
The larger spark helps starting, economy and power.
Regards,
Thomas
Melting Slicks
Joined: Aug 2003
Posts: 2,135
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From: Dayton Oh
You'll be just fine running at 35 or 40. With your HEI you shoul have no problems going up to the 40. The larger the gap then the more flame you'll be using to ignite the fuel mixture. I'm running a Mallory HEI and set my plugs at 40. Your ignition system and wires will have more to do with the gap that anything else since you've got to have enough energy to shoot across the plug.
