And, here is the reason for the iffy longevity that some posters have reported. There's been arguments/debates over what the issue really is. But, I posted on this after talking to Jerry in 2010.

Those tiny holes you see are where the oil has to drain back into the pan. If they get clogged, oil pools in the cylinders and starts creating the havoc -- that eventually leads to engine failure.

It's why I would be cautious about doing anything like: using engine cleaners, running heavier than recommended oil, skipping an oil change, or adding things like teflon treatments to your crankcase.

I believe these holes are either fewer or smaller than idle (compared to other engines). It doesn't mean the engine can't work or last a long time -- just that dilegence to recommended maintenance is the key to success.

I would think doing anything like this would benefit by balancing/rebalancing the rotating assembly -- though doing it equally to all cylinders SHOULD minimize the impact.

The fact that this mod is even mentioned is the biggest tell-tale to me -- but it's nice to see this posted as a way to improve any rebuild effort.

Thanks for posting!