Gearheads love horsepower. Many of them lust after an ultra high-power supercharged engine to build an extremely radical ride. Every once in a while however, someone comes along who just wants the sound and glory of a blower sticking through their hood. To hear the whine of it as they motor down the road is their ultimate source of satisfaction. They like the power it brings, but they're not looking for the max. They want a blower motor on a budget. That is where this engine comes in.
Typically, when talking about high-performance engines, using the terms "blower" and "budget" in the same sentence is considered an oxymoron. However, the crew at Hardcore Horsepower LLC has worked many late-night hours seeking the best combination of supercharged power, sights, and sounds for the street while keeping the total price relatively low.
The foundation for this budget blown engine is a reconditioned Chevy block with four-bolt main caps and ARP bolts. The block is CNC-machined to ensure the most accurate dimensions, and the factory one-piece rear main seal is converted to a two-piece design to make crankshaft and oil pan selection more plentiful. The machined block is then washed and professionally blueprinted for assembly with new cam bearings, brass freeze plugs, and hardened steel dowel pins installed.
The stroker crankshaft used in this 383 is an internally balanced Scat-9000 iron piece straight out of the box with one important modification. Small-blocks that run belt-driven blowers have a bad habit of spinning the harmonic dampener right off the crank. To prevent this, an extra keyway is cut into the crank snout and a matching keyway is cut into the dampener. Most high-performance dampener manufacturers offer double-keyed blower units.
Wiseco's Pro True blower pistons are forged from 2618 aluminum and feature coated skirts and full-floating pins to keep them reliable. The pistons hang on 6.0-inch Scat 4340 forged I-beam connecting rods with bronze bushings in the pin end and 3/8-inch ARP rod bolts in the big end. Wiseco also supplies its GFX moly-rings, which are file-fit to each bore. This engine will not be run at high rpm or high boost levels, so there's no reason to add the expense of H-beam rods or larger-diameter capscrews. The pistons and rings take the brunt of abuse in a blown engine, so extra money is spent on them instead.
Canton Racing supplied the 6-quart-capacity oil pan without side kick-outs making it easy to clear big headers. The pan also features a built-in crankshaft oil scraper, trap doors, and a windage screen for oil control and power. The oil pump is a high-volume Melling unit with a welded pick-up tube for added protection. The pump was bench-tested at 60 psi before installing and later rechecked in the engine to confirm that it was consistent.
In keeping with the budget theme, World Products S/R Torquer iron cylinder heads were used. The small-port World castings are stronger and can support higher power levels than OEM units. Bigger ports are not necessary for this type of engine, and the Weiand blower manifold matched up perfectly. To ensure a good seal, Mr. Gasket's Solicor head gaskets, which are derived from high-boost diesel engine technology, were installed. Mr. Gasket also sealed the intake to the heads with polymer Ultra Seal III gaskets. These high-density gaskets are developed for steam, oil, and chemical resistance and seal well with the low clamping loads typical of an aluminum manifold. Their high torque retention and high blowout resistance make them ideal for supercharged engines.
Most customers want their supercharged engines to surge like high-power drag cars. Traditional blower cams are ground with a wider lobe separation angle, which actually creates a smoother idle in a motor like this. Instead of running a blower cam, they choose an Erson hydraulic stroker grind with an advertised duration of 296 intake/306 exhaust and 0.503/0.503-inch net valve lift with 1.6-ratio rockers. The cam has a 110-degree lobe separation angle with 4 degrees advance built in and just enough overlap to make it sound great idling around and not affect driveability. The cam is big enough to make good power, but being a hydraulic flat-tappet, it's easy on the wallet.
Comp Cams High Energy 1.6:1 aluminum rockers were installed for durability and ease of adjustment. These low-friction rockers keep oil temperatures down, and their poly-lock nuts are easier and quicker to adjust than OE-style friction nuts.