i did mine like that, some of the later oval port heads don't have much meat on the outside to drill thru, so i drilled on the angle over too the headstud from the face of the head.. worked a treat..

The newer heads don't have room to drill straight up + straight over. Here's a pic:

Early Head:



Late Head (no boss):

Yep, 1 hole is all it took. Actually it has a better lubrication than before. Like you said, the oil now shoots straight up the 45 angle hole than 2 holes. Cheers. :)

just have to use caution and not use too much angle and break thru the outside... !!!

Is it like this? I think this head is drilled 45 degrees.



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