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131 0205 Proj02 Z

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Unless you work at the Tonawanda, New York, assembly plant, this is probably the first time you've ever seen the new Vortec 8.1L (that's 496 very nasty cubic inches) big-block on an engine hoist. This one came to us directly from Chevrolet, but it's rumored a GEN VI crate engine from GM Performance Parts is in the works. In the factory HD truck trim these mills produce 340 hp and 455 lb-ft, but in our nonemissions marine trim (no smog pump, no EGR, a set of headers, and a trick new EFI controller) it puts out an estimated 420 hp and 505 lb-ft of torque. Here you can see how we routed the original serpentine belt to work without the A/C compressor or smog pump.