A lot of good advice here. As far as your fuel pressure, it should not bleed at all for at least 5 minutes, mine doesn't move until at least 15. The factory injectors and regulator are notorious for causing starting, stumbling, and general fueling issues. I'm running 24lb LS1 injectors and a regulator for a 350 in mine and it loves it. They actually run about 28lb, since the 24lb rating is at 3 bar and with that regulator I'm running 4 bar. I run NGK TR55 plugs gapped at .045. I have tried pretty much every brand, heat range, and metal type there is in the past 3 months, and those are by far the best ones. The Delco platinums did second best, but wore out faster. I went 250-300 miles on each set of plugs. Would have saved a lot of time, money, and headache just sticking with the TR55s in the first place. If you're not comfortable knocking the gap down that much on the long ground strap the TR55 has (I believe they are pre-gapped at .060), the TR5 is the exact same plug with a shorter strap, I believe its pre-gapped at .035. Also, your small blocks seem quicker because they're not pushing nearly the weight of that CCSB. My Sierra is 4600lbs with me in it. My last dyno run was (unknowingly) run at 12 psi below spec fuel pressure and a pinion bearing trying to weld itself together. Crank power was 325/438 (factory is 290/410), which doesn't seem like much, but thats right around what an early 6.0 pushes, and in a lighter truck. Even then I was embarassing every Mustang and rice rocket that wanted to roll, and wasnt outrun too badly by LS1s. And the LS trucks couldn't touch me, either. I'll have it re-dynoed soon now that my axle and fuel pressure are fixed, but my point is that without about another 40-60 horses and ft-lbs, it will feel slower than your halfies or SUVs, but that's completely possible without a lot of cash.
