Modifying And Welding a Cast iron head

ok well here are some pics of what i was thinking...

most guys run a 1.70/1.44 valves but the old rule i hear is the exh is 80% of the intake in size and flow SO a 1.8/1.44 should be perfect... the worm clamp is just over a hair @ 1.75"

now i made some slight changes to the chamber, trying to slim down the cc's and also smooth it some... THIS IS MOCK UP!! lol and yes that is caulking...

now for the tubing idea the ports are at a sharp and versus the deck

would i have to have the tube installed at that angle to help with sharp angles after install??

thx guys