Canada1 Has got the right idea. All my heads on my cars have had extra oil ways drilled and also the casting on the head near the rockers has been filled down to allow more oil around them. I also have roller rockers in one of my heads and never had a single issue with any cam shafts that have been fitted over the years from CVH35 to Newman whats init now.


You might be able to spot some differences if you look closely.