Anybody with an EDGY head have plug recomendations?

[drillmastertommy]

Just sitting here hoping our weather is going to get better soon so I can get my Plymouth sorted and was wondering if anybody here runs an EDGY cylinder head (I know there's a few) and if so can anybody make a spark plug recommendation???

I'm just about to clean up and replace a few engine parts and I want to put in new plugs........ Thoughts, experiences?....

[greg g]

didn't edgy make a recommendation??? When I had my edmunds head on, it required a longer reach plug as the head casting is actually thincker than the sotck head. I can't remember the plub number but the heat range similar but with the longer reach.

[hkestes41]

Directly from the man himself when I questioned about plugs / torque for my head.

I used autolite 303 spark plugs. I like to torque the head to 60-65 psi and retorque a couple times when its cold. i use fel-pro gaskets and spray both sides with permatex coppercoat, making sure you have good coverage. And last, I highly reccommend using head studs instead of bolts. If you use bolts then maybe only torque to 55psi, Later, Earl

And just an FYI when I asked him about the internal by-pass since his head is not drilled for the by-pass.

Hello, yes, use the gasket as a template then drill at a slight angle into the head. Earl

[drillmastertommy]

Thanks for the replies. I did ask Earl when I bought the head but for all the things he is brilliant at, email replies aren't high up the list.

I shall start tracking down some auto lite plugs, they aren't an off the shelf brand over here.

I will also have to pluck up some non drink fuelled courage before drilling into my cylinder head but I suppose needs must.....

[Rusty O'Toole]

Suggest you use anti seize on the plug threads to prevent sticking. Likewise on the head studs, use milk of magnesia it is a common problem on aluminum heads on old cars, the head and studs grow together over the years making the head almost impossible to get off.

[hkestes41]

Thanks for the replies. I did ask Earl when I bought the head but for all the things he is brilliant at, email replies aren't high up the list.

I shall start tracking down some auto lite plugs, they aren't an off the shelf brand over here.

I will also have to pluck up some non drink fuelled courage before drilling into my cylinder head but I suppose needs must.....

I know what you mean, I studied and studied and measured and studied some more before drilling a small pilot hole which then ran a larger bit then a larger bit before an even larger bit until it was a big enough hole.

[Jim Shepard]

I just bought a set of 303's at Car Quest. Their part number is FRA 303. $1.87 each...

[Frank Elder]

Scroll down to near the bottam of the page.

http://uk.sparkplug-crossreference.com/convert/AUTOLITE/303/

[Plymouthy Adams]

as the head casting may be different on your head compared to ohter cast heads, I would caustion you to do an exact measurement and ensure that no threads enter into the compression chamber. To explain this position I will draw from some experiences many people had years ago with such things as one size fit all plugs with fancy electrode tip design..best I can do without calling names...these plugs were installed per their fit all chart per model and had threads extending into the compression chamber..the plugs got extemely corroded/carboned up and on the process of removal would destroy the threads in the aluminum head..this should be all that I need to say on the subject...

[Rusty O'Toole]

as the head casting may be different on your head compared to ohter cast heads, I would caustion you to do an exact measurement and ensure that no threads enter into the compression chamber. To explain this position I will draw from some experiences many people had years ago with such things as one size fit all plugs with fancy electrode tip design..best I can do without calling names...these plugs were installed per their fit all chart per model and had threads extending into the compression chamber..the plugs got extemely corroded/carboned up and on the process of removal would destroy the threads in the aluminum head..this should be all that I need to say on the subject...

Tim this is a good point. I ran into the same exact problem years ago on VW engines. Every once in a while you would go to take the spark plugs out and they would rip the threads right out of the head. It turned out, Champion spark plugs are a hair longer than the OEM Bosch. They stuck into the combustion chamber just a bit. If you left them in too long they would get a buildup of hard carbon on the end that would take the threads right out of the head as you unscrewed them. I put it down to a metric length vs inch length. You used to get much worse deposits years ago with leaded gas.

[mpn23748]

I use Autolite 425, if I remember correctly the threads in the head are 1/2" and the 303 only has 3/8" of thread.

[drillmastertommy]

I think it's probably time to measure the depth of the thread in the head........ If the thread is set to take a 1/2" plug, is running a 3/8" plug going to have a detrimental effect?

[greg g]

you dont wat either the electrode shrouded by threads, nor do you want the plug threads exposed below the threads of the head. Nor do you want the electrode to interfere withthe piston of valve. In the stock heads, the plug is located over a valve, in some of the aftermarket alumium heads the plugs are centered in the head and may be over the piston. For those installing after market of heavily milled stock heads, I would install a plug int the head prior to installing the head on the car to assure that the plug fit/extension is correct.

[drillmastertommy]

For those installing after market of heavily milled stock heads, I would install a plug int the head prior to installing the head on the car to assure that the plug fit/extension is correct.

That sounds like pretty sound advice. I'll be taking the head into the workshop next week to drill the internal bypass so I'll make sure I fit the right plugs then.