This article has a lot of pictures that show the paths of engine oil flow in an Olds 350 block, very informative and worth a look. It talks about oil restricters, etc... I'm not sold on the use of restricters, but the article discusses the positioning of the restricters for those that are interested:

http://blog.wrenchmanrepair.com/cate...mobile-engine/

 

Pretty much what I've been saying for decades. Note that contrary to what the article implies, most people install restrictors with the intent that they will reduce oil flow to the rockers and top end. THE DO NOT. In fact, as I have noted in prior posts and as noted in the quote above, the popular cam bearing restrictors actually INCREASE oil flow elsewhere, which meant that if you do nothing else, they will INCREASE oil to the rockers. Not what people want or need. Throw them away.

By the way, if you keep reading on that page, he goes on to say that he isn't sure Olds made 455s in 1968...

 

And for an article like this his language isn't the best either. I'm no saint but he certainly doesn't mince words.

 

That's Tim McDaniel's page. He's a transmission guy. Builds TH400's for dirt, derby and roundy rounds.
He used to be on ROP as Mad Bomber.

 

There may have been some good information in there. I couldn't tell because the guy's illiterate. Thanks for posting, though.

 

Today's cam bearings that I have bought have small enough holes in them already. No restrictor is called for. Additionally, the restrictors in the lifter feed holes are not needed if the lifters meter the correct (small) amount of oil to the rockers. We are much better off today with the Melling 22HV pump; it flows a lot more than the old stock pumps. OTOH, I have a Mondello pump from the 1970s with his hard anodized box pickup for the Toro pan, and it gives plenty of pressure with well designed hydraulic lifters.