1970 454 correct spark plug
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Burning Brakes
Joined: Mar 2008
Posts: 809
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From: brewster NY
1970 454 correct spark plug
As the title states what is the correct spark plug for a bone stock 1970 454/390 hp motor and where is the best place to by them and if I can"t find these whats the best replacement. Thanks
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From: Cape Cod, Mass.
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You may like a 5 heat range plug better. I find it a little more responsive in both my small blocks and my big block. In my 68 427/390 I run AC R45XLS and the car really likes it. If your engine is bone stock you should not have any problem with an extended tip plug.
Drifting
Joined: Aug 2003
Posts: 1,327
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From: Fl
I thought the R44t R43T plugs were tappered?
They don't use a washer on the bottom.
The XLS plus use a washer adn are designed for non tappered seat.
I think they were used on the 71 LS6 engine and the 1970 LS6/LS7.
I can't speak for BB engines 1969 and prior.
They don't use a washer on the bottom.
The XLS plus use a washer adn are designed for non tappered seat.
I think they were used on the 71 LS6 engine and the 1970 LS6/LS7.
I can't speak for BB engines 1969 and prior.
