iridium spark plugs for outboard?

[Nick0151]

Hi

looking at the recommend spark plugs for my 82 evinrude 70 they suggest two one for low speed and trolling and another for high rpm I have a set of the trolling ones can’t remember of the top of my head but the ones for high RPM are QL78v and are kinda hard to find..

Are iridium plugs an upgrade to an outboard and will they be worth the cost difference. Will the be a noticeable difference?


thanks

Nick

 

[racerone]

If your motor is in good condition it will run fine with L77J4C.----Will troll all day long.

 

[Nick0151]

That’s the ones I have why do they recommend the QL 78V for high RPM?

 

[fdrgator]

My opinion only---they came out with surface gap plugs years earlier with big hoopla. Then they found out that they were ok for high speed running but gave problems at slower speeds. (Q)L77jc4 were a lifesaver in the situation. I think marketing, or pride or perhaps something else makes them hang onto some old thinking(????) Ok, supposedly surface gap plugs might be less prone to pre-ignition at high RPM if you want to go that argument.