LA small block,Do you put an oil passage in your head stud?
The answer seems rather obvious to me & it would not be to notch a fastener & create a failure point. Enlarge the current hole in the head by 0.010". The hole is already larger than 0.5" to allow for stud/bolt clearance, but not knowing the actual OD, I used 1/2" [ 0.500"] as a reference. Going from 0.500 to 0.510" creates a gap increase equivalent to a 0.072" hole. Since the starting point is greater than 0.500", the hole size it creates will be considerably larger.
That would work if you could insure the hole you drill with a drill bit and not in a mill would end up centered around the stud. Dave did think of that but the heads were new and cost Almost $4000.00 .
After talking to Indy on Warranty that decision was a no.
Then the next was re route the oiling. T&D said a spray oiler shouldn't be considered for use on the street with the spring tension we were using with their rockers and shaft.
ARP was called to see if they made a stud for this application. They did not but gave Dave the idea. So Dave Measured the stud shaft and then the inside of the threads and came up with this method.
Why cut the whole stud when a passage would be a more direct way to go. He had a bunch of studs so he did one and over torqued it and it held without an issue on a trial. So he did 2 of my new studs.
I never had a problem for over 8 years and used them over once and will use them again with 13.5-1 comp.
Why modify $4000.00 parts when you can modify a 2 of a $100 set of 20.
Yout method may work and there may be several others that would also work. This is the method my son is using on all heads Iron and aluminum.
He won't try and tell someone he is drilling their new heads and be responsible if they fail for any reason to replace them. Could you imagine what a head manufacture would say when trying to return them. Just thinking ahead when building engines with parts paid for by the customer.
Exactly what Dave did years ago for us. Don't take someones new heads out of the box and run a drill bit through them. If you own them I guess it would be your call.
But thanks for the input Its a chance it would work on your own heads.