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Like to get as much info on this as possible every little bit of info helps can anyone enlighten me on plug gap what gap should you run for what setups and hot plugs colder plugs and what there use is many thanks
This is a rather complex subject.
The basics are:
The largest gap you can run without any misfire - going to depend mostly on the voltage the ignition system can reliably provide and the boost the engine is subject to. this can be anything from 0."060 (1.5mm) (or even 0.080 in one instance!) for some OEM engines down to 0.015"for some high boost on standard ignition. This is something you'll need to sort out for your particular application, as there's a lot of overlap - especially with some of the more powerful aftermarket options!
I believe André has commented on plug selection, but you seem to be asking about what 'heat ranges' are.
An IC engine will produce little particles of mater that are deposited on the spark plug, especially the insulator and electrodes, and by selecting the correct heat range spark plug it will get the insulator tip and electrodes hot enough to burn them off - however, get them too hot and you can melt them or, worse, cause problems like pre-ignition (the plug is hot enough to ignite the charge before the spark does) that can rapidly destroy an engine. because engines are different, and have different requirements for getting the correct temperature, there are hot/softer spark plugs which have a long insulator path that takes less heat from the spark plug tip, and colder/harder spark plugs that are designed to pull more heat from that are - the spark plug will run hotter or colder.
With modified engines, especially those with forced induction, there is more heat produced in the engine's cylinder and so colder spark plugs are required to pull that heat from the spark plug tip - for a mildly modified engine, one grade colder may suffice, for an engine running a lot of boost and/or using 'exotic' fuels 2, 3 even 4 grades colder may be required.
As an aside, under extreme conditions it may be impossible to pull the heat out of the ground electrode - that's the side one - and there are special race spark plugs that don't even use them - also handy with very high compression pistons as there isn't the clearance issues that can arise.
Ok i belive you are correct on Andre covering that im new to hp academy been hamming down on the courses its alot to take in and remeber it all i was just curious i read an article about a guy who gapped and clocked all the plugs so they were all in the same position in the cylinder head and it claim there were power gains but i dont think it was large number or how true that was but it was interesting. Thank you for the response!
Clocking the spark plugs refers to selecting the spark plugs to all fit with the earth electrode in a specific orientation in the cylinder. Don't know if they' re still available, but you used to be able to get different thichness washers for this.
Pro-built motors pay attention to "indexing" the plugs. I often see a sharpie marker on the plug insulator inline with the electrode gap.
As David said, same thing, different name.