Bet that engine will not have a long life.
Probably scream like a two stroke.
Be fun to thrash, but it would die young.
My motto is that if you need to eek out every drop of power, then you simply need a bigger motor.
That comes from being involved in, VWs, Ultralight aircraft, and homebuilt aircraft too long, and watching people try to make a little engine as powerful as a bigger engine, and seeing the results.