Spark Plugs for MR1

[BlkGS]

Historically I've always used the NGK plugs, but in all my vehicles I usually use Autolite spark plugs, they work well in my cars and are well priced (with hella awesome rebates.

Anyone used them? Autolite claims the 4302 will fit, Rockauto has the xtreme sport plugs for $3.66 each, with a $2 rebate per plug for Iridium plugs.

 

[Compatico]

Historically I've always used the NGK plugs, but in all my vehicles I usually use Autolite spark plugs, they work well in my cars and are well priced (with hella awesome rebates.

Anyone used them? Autolite claims the 4302 will fit, Rockauto has the xtreme sport plugs for $3.66 each, with a $2 rebate per plug for Iridium plugs.

I don't recommend using "compatible" plugs. While they may fit the threads and have the same length to enter the cylinder and same temp rating, you need to make sure you use iridium plugs as these engines rev high and hot. Totally different running environment from cars that mostly run at 1500-2500 rpm compared to Yamaha marine engines that run at 5000-8000 rpm for hours at a time. Iridium is used as it has a much higher melting point.

 

[BlkGS]

I looked it up a bit more and found the rebate for the autolites ended at the end of 2019. Still a little cheaper, but probably not enough to worry about it.

Good note about the Iridium plugs, I had figured since they get swapped out every year copper plugs would actually work better, but I'm glad to find out why that's not the case before I tried it, haha.