Did a little intake work Tonite...

Do you mean that the tubes from the rear of the manifold to the front would lower the temperature at the back of the heads?
Because if you have a 16 pound pressure cap on your radiator, your going to have 16 lb throughout the system I would think.
It (will) help circulation, and it (will) help when filling to get the air out. The lines between the cyl. do help w/ cooling the head more evenly. I did it on my 600 horse street n strip sbc engines . If I ever have my 440/505 stroker out, I might take a look at doing it to it also, but don`t think I have room w/ my external oil lines and 2 " headers in the 68 barracuda body.