the carb fixes the bottleneck issue of power with the crappy spider injectors. unless you go to a marine intake with up-sizable injectors to dial up more fuel, you're pretty much maxed out on how much power you can make once you max out your spider injectors. however, there are issues that arise from going to a marine intake as well as far as i think you lose cruise capability, but also have to have it computer tuned everytime you make a change. (i understand some people are savvy at that, and it won't be a recurring cost.) i've talked to several people in the biz (mechanics, machine shop hot rod gear head types, etc) that a vortec long block with a mild cam and flat top pistons, set up properly, would have no problem seeing 400 hp. sucks that they're so lame from the fuel injection system they put in them. there's simply not the headroom to turn up the power in the vortec 5.7's as there is in let's say, the LS motors, because the fuel bottlenecks it down so bad. from a good tune, maybe a CAI, people have gotten like 40+ hp on their LS motors. from what i remember on the 5.7's, a tune has yielded what, like 10? 15? and this isn't turning into a vortec/lsx debate, just saying that if you're not able to put more fuel in, (to a point, mind you) you can't make more power. i know that a lot of people look at going back to carb like it's going back in time, may as well put wagon wheels on your car, etc., but carb will make more power in this particular application because it's able to deliver more fuel. and the nitpickers will say, oh well a tune on my 5.7 does increase the fuel, yada yada, but the small poppet injectors we have on our 5.7's just won't keep up with removable, upgradable, externally mounted injectors. hence the reason people who try to make big power with the vortec 5.7 and keep fuel injection go with the marine intake, because of the ability to make injector changes easily.
