Ribbon delete and spark plug gap adjustments?

[Swatski]

It was just posted on jetboaters site, something I don't think I have heard before - that you are supposed to adjust the spark plug gap to get maximum benefit from ribbon removal.
I am very curious about this.

(SX240 is one of the twin engine 1.8l N/A Yamaha jet boats).

"If you delete your air box like I explained above, maximize your Gap to account for the additional fuel/air. The Gap on my SX240 was set at .040, not the recommended .031 -.035. She ran perfectly. As a matter of fact, with a few other minor things I did to the boat, I could run 55 - 56 mph in perfect conditions."


The post #31 here:
https://jetboaters.net/threads/riva-...er.2632/page-2

[Green Hulk]

I've never heard of this being a requirement and I've never had to open the gap on any of my ski regardless of any mods, including my turbo skis. They all run perfectly strong.

[Swatski]

That's kind of what I thought. Thank you!

[Aquaholic6801]

Now indexing the plugs used to be worth around 50 rpm back in the 2 Stoke days.....

[Swatski]

That's right! So, has anyone tried it on the 1.8l? And would indexing plugs possibly give some positive results?

[ISLANDRACING]

That's right! So, has anyone tried it on the 1.8l? And would indexing plugs possibly give some positive results?

possibly

...that 10-20-30 rpm you may blip here and there may very well be the difference between 1st and 2nd place.