Originally Posted by themyst
People have tried tighter gaps using NGK plugs with no success fixing this specific issue.
What about a tighter gap on stock plugs?
I dont recall too many V4 maps having read me files, most of them were posted here back in the day with instructions. It's been so long.
OP you might want to look into a rev 2.5 upgrade, it has many benefits including extra fueling capacity and better tuning.