Horsepower!
Amir Rosenbaum, Ontario, CA
Previously, we’ve divulged the technical details behind Spectre Performance’s Speedliner streamliner land-speed race car. In 2010, the twin-turbo, Cadillac-powered car broke the 400-mph barrier at Mike Cook’s Top Speed Shootout, making it the fastest gasoline-powered, wheel-driven car in history. Well, behind every great streamliner, there’s a great push vehicle, and here’s a peek under the hood of the Chevy dualie charged with setting the Speedliner down the path toward land-speed history.
Yeah, it’s obvious this is a turbocharged vehicle, but you have to look past all the intake plumbing to the lopsided, front-mounted distributor to see this Chevy truck isn’t Chevy powered. That is, in fact, a 500ci Cadillac engine, one of the Speedliner’s spare engines. Like the Speedliner, twin turbos force-feed this big-cube monster to power numbers soaring past the 1,000hp mark.
Turbos: The pair of Garrett turbochargers is fed on both the intake and exhaust sides by custom plumbing made by Performance Fabrication. The inlet plumbing leads to an intercooler neatly hidden within the upper plenum of the custom Hogan’s sheetmetal intake manifold.
Fuel: This combination of large displacement and big boost requires a lot of fuel. An Aeromotive pump delivers fuel to sixteen 82-pound fuel injectors. A FAST fuel injection system makes it all happen.
Block: Big-inch Cadillac specialists Cad Company built this monster for Spectre’s owner, Amir Rosenbaum, using a production block and crankshaft. You read that right—a stock-stroke production crank! The bore is 4.360, the rods are from Eagle, the pistons are from Venolia, and the compression ratio is 9.00:1. The heads are also stock but were tuned up with some basic hand porting and larger, 2.25/1.90-inch valves. The exhaust valves are made from Inconel, a particularly heat-resistant steel alloy.
The 472/500 Cadillac Engine
The 472 engine debuted in 1968. With a 4.30-inch bore and 4.060-inch stroke, it was GM’s answer to Ford’s 460- and Chrysler’s 440-powered luxury liners. Cadillac upped the ante just two years later with a stroke increase to 4.304 inches, and the resulting 500-inch plant was the biggest production V8 to date. In the era, the 10.0:1 versions made an impressive 400 hp and 550 lb-ft. Unfortunately, the ’71’s drop in compression to 8.5:1 killed the fun, and these poor bastards struggled to make 220 hp and 385 lb-ft. GM mercifully dropped this engine from Cadillac’s lineup in 1976, replacing it with a smaller-bore 425 engine. That was followed with the infamous V8-6-4 368ci nightmare in 1980.
Want a 472/500? Look for these behemoths in ’68 to ’75 Caddys. The Eldorados got the 500s while the rest of the lineup got the 472. Don’t overlook the smaller-displacement version. Five hundred inches is a crankshaft.