We have put 340/360 heads on 318's and have yet once to have it cost us performance, but in fact always a nice gain... but what do I know :rolleyes: I don't even like my own advise!!! :D
Did you order this stuff ?
I have the 6900 in my 73 W200 360 with Holley 2 barrel. lol
It was a good upgrade from the factory cam. works good with the 4.10's and loadflite.