Which if I remember correctly is enough to handle a bit over 400 hp at the crank without going to 100% duty cycle.

If an N/A Crossfire were to benifit from larger injectors, I think that TVT_DESIGN is correct in going up to 17 lb injectors, another step up would be 19 or 20s. This would leave additional 'head room' without harming the idle. (NOTE: This is my opinion and not based on actual hard numbers. Feel free to break out your calculator or spreadsheet... )