Need a recommendation on the spark plug gap with acel super coil.
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Supreme Member
Joined: Sep 2001
Posts: 4,231
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From: Manassas, VA
Car: 89 Formula Firebird
Engine: 305 - Demon 525
Transmission: 700R4
Need a recommendation on the spark plug gap with acel super coil.
Am I right to say that for a stock coil .035 would be good but on an acel super coil HEI OEM replacement .045 would be more ideal?
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Joined: Feb 2005
Posts: 1,054
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From: Ajax, ON
Car: 85Z28 87GTA 91GTA 98SS
Engine: SBC, LS-x
Transmission: T-5, 700-R4, T-56
You might get a trillion opinions on this. .045 should be fine. I'd be satisfied with anything between .035 - .045. Gap them so they are all the same.
.040-.045 would be just fine. Make sure you buy plugs that are designed for a gap that wide. Stock replacement plugs that are designed to work with a .035 gap won't work for a bigger gap- the electrode would no longer be anywhere close to parallel with the top of the center electrode- that's bad.
For a stock cast iron SBC cylinder head a good starting point for a plug that could take a wider gap look at an Autolite 24 (or equivalent from other manufacturers).
For a stock cast iron SBC cylinder head a good starting point for a plug that could take a wider gap look at an Autolite 24 (or equivalent from other manufacturers).
Thread Starter
Supreme Member
Joined: Sep 2001
Posts: 4,231
Likes: 1
From: Manassas, VA
Car: 89 Formula Firebird
Engine: 305 - Demon 525
Transmission: 700R4
Originally posted by Damon
the electrode would no longer be anywhere close to parallel with the top of the center electrode- that's bad.
the electrode would no longer be anywhere close to parallel with the top of the center electrode- that's bad.
They are autolite, I cant remember the 20 something number. I didnt have a gap gauge at the time so I eyed it out and matched it to the best I could to the old plugs to just try and get the engine started after a long process. Yea I know, but I just wanted to hear it start after working on it for 3 weeks. TGO Supporter
Joined: Jul 2003
Posts: 4,803
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From: Grand Rapids, MI
Car: Z28
Engine: Sb2.2 406
Transmission: Jerico 4 speed
Axle/Gears: Ford 9" 3.60
Originally posted by Red Devil
You'll see a bigger return on indexed plugs over a bigger gap... not that you'll see much with that either.
You'll see a bigger return on indexed plugs over a bigger gap... not that you'll see much with that either.
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Joined: Jul 2001
Posts: 3,974
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From: Pueblo Co
Car: 1989 C4
Engine: L98
Transmission: 700r4
Axle/Gears: 307
Originally posted by Damon
.040-.045 would be just fine. Make sure you buy plugs that are designed for a gap that wide. Stock replacement plugs that are designed to work with a .035 gap won't work for a bigger gap- the electrode would no longer be anywhere close to parallel with the top of the center electrode- that's bad.
For a stock cast iron SBC cylinder head a good starting point for a plug that could take a wider gap look at an Autolite 24 (or equivalent from other manufacturers).
.040-.045 would be just fine. Make sure you buy plugs that are designed for a gap that wide. Stock replacement plugs that are designed to work with a .035 gap won't work for a bigger gap- the electrode would no longer be anywhere close to parallel with the top of the center electrode- that's bad.
For a stock cast iron SBC cylinder head a good starting point for a plug that could take a wider gap look at an Autolite 24 (or equivalent from other manufacturers).
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