well if your target is 630-640whp, i think a set of 725cc injectors should be good for your goals. So if you don't want to spent too much just yet, you can just get a set of injectors. If you want more room for more power in the future, 850cc and a bigger fuel pump should be enough. Do note that the bigger injectors you put in, the more fuel consuming it will be.
This is the link to the forged performance build.
Forged Performance: 636whp G37 Coupe!!! - MyG37
The dyno is done on dyno dynamics, so not the feel good once like dynojet.
As for turbo, it's the greddy G20 kit, so it will be which ever turbo that came with it. Should be similar to the GT28.
Also they used 725cc injectors, so if your power goals is similar, it should be enough.
BTW, are you getting 94 from husky? i thought about going on a higher tune, but after reading up on the amount of ethanol they use to boost oct number, i ended up sticking with shell 91 and take the decrease in power. Also i noticed that 94 from husky returns less mileage per tank then shell 91, have you had that experience? I'm in Calgary by the way, so no chevron like Vancouver
