spark plug ?

[48tony]

Hi all. after a long search for pistons and rings on my 1970 60 hp johnson.The pistons i ended up getting are glm aftermaket 30 over.this motor being the lopper style it has slightly domed pistons.The new glm pistons are flat on the top.Being a lower comprestion piston do to todays fuel vs in 1970 with the fuel octain difference.The plugs i ran before this rebuild were the champ-l77jc4. Should I stay with this plug using the new piston.And does anyone out there have any feedback on glm products.I was really in qustion with this piston not being the dome style.But the guy i went through to get them told me they would work out fine.

 

[haffiman37]

You may do a test with QL78YC.
Just be sure pistons do not hit!!!

 

[Boobie]

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