Well, finding out what the C5 needs to run correctly would behoove you before slapping it in. When it comes to fuel, more isn't better, but too little is very dangerous. With bolt-ons, you won't require more fuel than the stock equipment. You need to be very aware and able to control your fuel when you have a very built N/A motor or FI. You also don't want to starve an upgraded motor so find out what the OEM fuel pressure, injector size (if applicable), fuel line specs (in some cases), and fuel pump LPH specs are.