what gives

On the left is a rocker shaft that came with adj rockers from I thought was a 273. On the right is a shaft from a 273 with solid lifters. Came out of my 66 273 charger engine. Now the reason for this post is I installed the adj rockers using the shaft on the left and I did not get enough oil flow to rockers. I have asked about this on other posts. I mean ran it 3 min and still almost dry. I can see the for sure 273 rocker shaft would oil better. What gives? I only have one shaft like the one on the right, when I got car the left head was missing. Thanks. MT:burnout:

The left is a regular hole shaft and the right is what they call a "banana groove shaft".....Naturally as you have pointed out the banana groove shafts are better as the rockers get better oiling.....Both types came on 273's....Although if you used the one on the left you should still get an adequate amount of oil to the rockers or something else is wrong as mentioned