OK, Jim,

Glad to be corrected to what is right, as ever. I glance through his columns, but didn't pick that up. If what I heard about KLOTZ doing additional filtration before they 'can' castor is right, it has always been a good oil, and that may help make it better.

Combat and other high-RPM engines flush enough fuel through that they may not heat to the point castor varnishing becomes a serious problem with ABC/AAC/ABN metals, and usually, to get to high RPMs, clearances are carefully developed, any way.

I chose not to name the fuel company, because their fuel is generally pretty good, and those of us who remember the original "discussion" needn't be retold about that. Newer guys satisfied with their fuels don't need to have it dissed, if it works for them. Just my rationalization...