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Discussion Starter · #1 · (Edited)
Have a mid-70's HEI on the 56, Power Pack 265 in my 55....Pulled one of the spark plugs.....It is an Autolite 86, which crosses to an AC 45....Also, it is gapped at .035. by the PO.

I believe the type plug is correct.....However, I think the gap should be set wider.....I've seen recommendations of anywhere from .045 to .060.

What's correct?
 

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i had that dist. in my `55. gap at .035. went to that "D.U.I." coil, gapped at .045. even had to richen it up.
 

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Have a mid-70's HEI on the 56, Power Pack 265 in my 55....Pulled one of the spark plugs.....It is an Autolite 86, which crosses to an AC 45....Also, it is gapped at .035. by the PO.

I believe the type plug is correct.....However, I think the gap should be set wider.....I've seen recommendations of anywhere from .045 to .060.

What's correct?
85 or 86 Autolite is the right Plug If you have the heads that used big Plug with crush washer.
The Fram Master Catalog (1993) has the gap at 45 for the 75 and up V8 Chevy's. Small plugs 75 up used Autolite 26 .
 

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Discussion Starter · #5 ·
85 or 86 Autolite is the right Plug If you have the heads that used big Plug with crush washer.
The Fram Master Catalog (1993) has the gap at 45 for the 75 and up V8 Chevy's. Small plugs 75 up used Autolite 26 .
Have the 60's PP heads, thus the larger AC44 or AC45 plugs....I'm thinking .060 is a bit much.....045-.050 would be more like it.
 

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Have the 60's PP heads, thus the larger AC44 or AC45 plugs....I'm thinking .060 is a bit much.....045-.050 would be more like it.
So that the right Plug for those heads. Just gap them at 45.
I bought a bunch of sets of autolite plugs when Roses was closing stores in NC. Must have 10 sets of autolite 85,s and 86's. They work in 283's or my Dodge wide block 318.
 

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Discussion Starter · #8 · (Edited)

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now i have an "external" cylinder type coil, uni-lite conversion, under the stock cap. i have my 45`s at .042. just a light gray tip on them.
 

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Discussion Starter · #10 ·
Thanks for the reply Dude :):tu
 
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