[Mr427]

Hi it´s me again!
Jim Dove is right on the money. I have no particular expertise on the very narrow subject of external versus internal balancing; benefits or demerits of either one.

However, I can state from experience that the external stuff can cause a lot of problems and burned dollar bills if you don´t know what you are doing. Once you have your engine together, WITH the external stuff and you KNOW it was checked by a reputable machine shop and given the go ahead.

Then you will know that you can stand on it at 6000rpm+ without concern. But as for us novices and amateurs, zero is the way to go.