Make sure you check out this '07 Silverado 2500HD in the March issue...

 It's clean, fast, gets 17-mpg, and is insanely well-kept. The owner washes and waxes it every Thanksgiving, then parks it in doors for the long, Indiana winter. With virtually every modification you can make on a Duramax before digging into the engine (lift pump, shimmed fuel pressure regulator valve, rerouted PCV system, EGR solution, air intake, Y-bridge, hot-side intercooler pipe, EFILive with DSP5 switch), it represents the everyday diesel owner's truck on that front. Thanks to some spot-on tuning, the factory CP3 maintains rail pressure even with a set of 45-percent over nozzles in the mix. Add in a 68mm Garrett 4094 from Danville Performance and a transmission full of Sun Coast parts, and you get a 600+ hp LBZ that's ultra-reliable and fun to drive. Just check out the time slip below, as it runs 12.20's at more than 109 mph and leaps off the line with 1.6-second 60-foots.