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Chevrolet Big Block Engine - The Big-Block From Hell
 7. The camshaft is a very...  7. The camshaft is a very aggressive mechanical roller, spec'd out by DNE and ground by LSM, that features the popular LS firing order swap, which alters the firing order of No. 2 and 3 cylinders and also No. 4 and 7 cylinders. According to Ebbert, who checked the camshaft after it arrived at the shop, the swap can make additional power with the right intake manifold and header combination. Dave had the camshaft custom-ground for this application and was remiss to mention the specifics. But, he did say lift at the valve measured more than 0.800 inch for both the intake and exhaust, and that the duration for the intake side was 270-plus and exhaust 280-plus degrees. The lobe separation is at 116 degrees.  8. The other half of our rotating...  8. The other half of our rotating assembly is comprised of parts from CP, Lunati, and WPC. The forged CP pistons feature lateral gas ports, a 1.300-inch compression height, and -0.180-inch dish. The ring grooves measure 0.043-inch up top and 1.5 mm for the second groove. The piston skirt also received an anti-friction coating from Embee. The forged Lunati Pro Billet connecting rods measure 6.700 inches long, and the small bushed ends swing on Western Wristpin 4340 chrome-moly wristpins. The 0.990-inch-diameter wristpins have a 0.180-inch tapered wall. The wristpins also feature a proprietary metal treatment process that, according to Ebbert, does increase the strength of the metal, considerably.  9. Akerly & Childs moly rings...  9. Akerly & Childs moly rings make up the pack. The narrow top groove is filled with a 0.170-inch radial wall ring. Groove No. 2 received a Napier hook groove ring with a 0.165 radial wall.  10. The machine work on these...  10. The machine work on these rods is incredible, and they only needed a minor touch-up on a polishing wheel to bring them into near-perfect balance. The small ends are bronze bushed, and the big ends are held together with 7/16-inch hardware from Lunati. The rod bolts were tightened, and the stretch was measured against Lunati's specs rather than relying on a torque spec.  11. A crankshaft scraper was...  11. A crankshaft scraper was employed to keep oil off of the crankshaft as it rotates, which will reduce windage and increase horsepower. It's held snugly in place, via the oil pan mounting bolts. The scraper was designed by DNE and Jordan Woods and is laser-cut from 0.040-inch stainless steel.  12a. A Titan Speed Engineering...  12a. A Titan Speed Engineering Sportsman wet-sump oil pump is coupled with an MSD oil pump drive unit. The Titan pump is a gerotor design that virtually eliminates high-speed cavitation, is fully rebuildable, and incorporates a large built-in pickup. The MSD part was necessary to connect the oil pump to the cam gear, because we'll be installing a Jesel front mount distributor, rather than a traditional distributor.  12b. Dave had to machine some...  12b. Dave had to machine some material off of the oil pump's case to provide adequate clearance for the No. 5 crankshaft counterweight. Once he was through making aluminum chips, the pump fit perfectly.  13. Stef's Fabrication Specialties...  13. Stef's Fabrication Specialties crafted the 14-quart, kick-out-style oil pan from 0.090-inch-thick aluminum that we'll use to seal up the bottom end of this motor. The pan features a Teflon-coated, uni-directional windscreen, designed to allow oil to flow into the sump area but not splash back up out of it toward the crankshaft. The pan also contains a pair of trap doors that keep the oil in the sump area during hard acceleration. A generous amount of gray silicone sealant was used to mate the oil pan to the block, rather than a traditional gasket. Care was taken, here, to make sure not only that oil wouldn't leak out but that the crankcase was completely sealed off to allow the vacuum pump to do its job.
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