[C2] ? on spark plug #
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? on spark plug #
I have a 64 coupe 350 with turbo heads #340292 w/angle plugs.My question is,what # plug would you recommend.It came with Autolite 26 tapered seat 5/8" socket size.Would like to change to AC Delco and would I use a tapered seat or washer seating with these heads.Thanks
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St. Jude Donor '07
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From: The Villages Fl.
It looks like a tapered seat and that's what type of plugs came with it.But it also looks like a flat washer seating.Pictures included but not to good.I am hoping that someone who has a set of these heads would know for sure,but I think they are a tapered seat.Thanks for helping me with some info.Alan
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St. Jude Donor '07
Mike
the ZZ4's aluminum heads have tapered seats, GM installed gasketed plugs in them...
there must be a reason, other than they had a bunch of gasketed plugs to throw away...
when I replaced them, I used tapered plugs
Bill
the ZZ4's aluminum heads have tapered seats, GM installed gasketed plugs in them...
there must be a reason, other than they had a bunch of gasketed plugs to throw away...
when I replaced them, I used tapered plugs
Bill
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The pictures the OP shows looks like a tapered seat
The spark plugs dissipate heat through the copper gasket to the head which is why the plug manf. recommend a specific torque setting. Use the wrong torque and you change the operating temp of the plug. Same thing for the tapered seat.
If you can interchange taper seat and washer seat spark plugs, it's news to me but there's quite a lot I've never heard before.
I bought a set of those 292 heads about 1975. Never used them, they're still in the factory wrappers on the shelf. I have looked at them a few times and best I remember, they were angle plug, tapered seat, 10 mm(?) long plugs, like a BB. Not sure though
It the OP does a google for "292 turbo heads", there's all kinds of chatter about them he can look up.
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From: The Villages Fl.
The OP doesn't have aluminum heads though. I know nothing about the ZZ 4 heads.
The pictures the OP shows looks like a tapered seat
The spark plugs dissipate heat through the copper gasket to the head which is why the plug manf. recommend a specific torque setting. Use the wrong torque and you change the operating temp of the plug. Same thing for the tapered seat.
If you can interchange taper seat and washer seat spark plugs, it's news to me but there's quite a lot I've never heard before.
I bought a set of those 292 heads about 1975. Never used them, they're still in the factory wrappers on the shelf. I have looked at them a few times and best I remember, they were angle plug, tapered seat, 10 mm(?) long plugs, like a BB. Not sure though
It the OP does a google for "292 turbo heads", there's all kinds of chatter about them he can look up.
The pictures the OP shows looks like a tapered seat
The spark plugs dissipate heat through the copper gasket to the head which is why the plug manf. recommend a specific torque setting. Use the wrong torque and you change the operating temp of the plug. Same thing for the tapered seat.
If you can interchange taper seat and washer seat spark plugs, it's news to me but there's quite a lot I've never heard before.
I bought a set of those 292 heads about 1975. Never used them, they're still in the factory wrappers on the shelf. I have looked at them a few times and best I remember, they were angle plug, tapered seat, 10 mm(?) long plugs, like a BB. Not sure though
It the OP does a google for "292 turbo heads", there's all kinds of chatter about them he can look up.
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From: Inverness FL
St. Jude Donor '07
The OP doesn't have aluminum heads though. I know nothing about the ZZ 4 heads.
The pictures the OP shows looks like a tapered seat
The spark plugs dissipate heat through the copper gasket to the head which is why the plug manf. recommend a specific torque setting. Use the wrong torque and you change the operating temp of the plug. Same thing for the tapered seat.
If you can interchange taper seat and washer seat spark plugs, it's news to me but there's quite a lot I've never heard before.
I bought a set of those 292 heads about 1975. Never used them, they're still in the factory wrappers on the shelf. I have looked at them a few times and best I remember, they were angle plug, tapered seat, 10 mm(?) long plugs, like a BB. Not sure though
It the OP does a google for "292 turbo heads", there's all kinds of chatter about them he can look up.
The pictures the OP shows looks like a tapered seat
The spark plugs dissipate heat through the copper gasket to the head which is why the plug manf. recommend a specific torque setting. Use the wrong torque and you change the operating temp of the plug. Same thing for the tapered seat.
If you can interchange taper seat and washer seat spark plugs, it's news to me but there's quite a lot I've never heard before.
I bought a set of those 292 heads about 1975. Never used them, they're still in the factory wrappers on the shelf. I have looked at them a few times and best I remember, they were angle plug, tapered seat, 10 mm(?) long plugs, like a BB. Not sure though
It the OP does a google for "292 turbo heads", there's all kinds of chatter about them he can look up.
I did a google search about which plug is correct and ran across a number of discussions about seemingly wrong plugs, and there seems to be no consensus as to why the seemingly wrong plugs are used in the wrong heads...
Bill
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From: Greenville, Indiana
That means it is not an extended reach plug like I have suggested.
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From: The Villages Fl.
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That's all I can tell you without looking at my heads and I'm not at home today.
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From: The Villages Fl.
I suggested the AC R45 TS in post #9. That's a tapered seat AC plug that the equivalent of the Autolite you have in there. That sounds about right if the thread length on the plug gets the firing tip into the combustion chamber.
That's all I can tell you without looking at my heads and I'm not at home today.
That's all I can tell you without looking at my heads and I'm not at home today.