440 Spark plug happy medium

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J1MMY

J1MMY

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Hello folks, helping a buddy do some jobs on his new acquisition and looking for a baseline recommendation on spark plugs for a 440 - mild cam, alloy heads (so 3/4” long thread) 750 Holley, Edelbrock RPM intake. Came with Bosch plugs (?!) which are long past their best, perhaps in part due to PO only really running the engine for brief periods. No real brand loyalty tbh. Cheers
 
Any clue on CR?

Likely you’ll want an NGK 5 or 6 heat range.

So, something like a BCPR5ES
 
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I would "start" with whatever stock plug for the year model. That way, you'll have a base line. You can tune from there reading the plugs.
 
PRH said:
What year big block came with “alloy” heads?
Click to expand...
Any that are fitted with Edelbrock RPM heads :p

Thanks folks, in between posting and catching up with replies I’ve done a little digging, found Edelbrock’s recommendation and ordered them for now. Not a fan of Champion plugs but it’s not my engine - I second the NGK preference
 
PRH said:
What year big block came with “alloy” heads?
Click to expand...

All of them, considering cast iron is technically also an alloy... lol never quite understood that slang term for aluminum heads, seen a lot of members on here in Australia and Europe say that.

Another vote for NGK's from me, that's all I use. Very durable and resistant to fouling.
 
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