Thanks for the comments guys.
The product I used is a silicone rubber #8421 from a company in Brazil called
Avipol Comercial Ltda. It costs about USD$15 a liter with the hardener.
Intake port profile looking down the port:
Actual port view:
Intake port profile showing valve bosses:
What do you make of that bump just above the valve seat?
Exhaust port profile:
The exhaust port goes tall where it has been pinched, thus maintaining the same port area.
I haven't burretted the ports, but when I was pouring the product in it was about 100cc for the intakes and 80cc for the exhausts.
Cheers,
Steve