You're making this into a much bigger deal than it needs to be - just use the regular Stage 4 map. Load up the map, edit the parameters to account for your injector size, and drive away. The car should be in closed loop the entire time, so the stock ECU will be adjusting to make sure you're getting a good amount of fuel. Plus you shouldn't be going all out WOT anyway. And its not like there's that much difference between a 16g & a VF30, and when you're off boost, they're the same.