Photographers have an oft-used saying: "It's not the camera, it's the photographer." We would like to adapt that saying to the world of performance engines, ergo: "It's not the engine, it's the builder." Readers of Super Chevy magazine may already be familiar with Smeding Performance and the 572 big-block that was built for the Project American Heroes 1957 Chevy, or the more recent July 2008 cover, which featured one of Smeding's blown crate small-blocks.
But that's yesterday's news. Recently Ben Smeding teamed up with the legendary Bill "Grumpy" Jenkins to build and produce a limited number of street-ready 572 big-blocks. Every Chevrolet enthusiast, young or old, is undoubtedly familiar with "da Grump." Since the 1960s, this Super Chevy Hall of Famer stomped the competition with his innovations and won championships with Chevrolet power.
When we first became aware of the Jenkins/Smeding crate engine, we were champing at the bit to be the first to cover this story, and we did just that. This monster-cubed 572 is in direct competition with the GM ZZ572 crate engine, but is this just another crate engine on the market? The short answer is no. Through the collaborative effort of Jenkins and Smeding, the street-ready 572 has patented piston redesigns, as well as numerous hours of dyno-proven R&D, testing and tuning by Jenkins and the Smeding crew. It's this R&D, testing, tuning and the results thereof that make this engine what it is. The test results at times were quite surprising. Various cam swaps, larger carburetors and larger intakes didn't necessarily yield larger results on the dyno, putting to bed the "Bigger is better" mentality that exists in most of our minds.
The bottom end of each 572, whether it is the fuel-injected or the carbureted version, is built in the same manner. The rotating assembly consists of a custom 4340 forged-steel, internally balanced crank, custom 4340 forged-steel H-beam, lightweight 6.535-inch connecting rods with full floating wrist pins, and custom-designed pistons by Jenkins and Smeding.
Take a look at the piston redesign that Jenkins and Smeding came up with. On the right in the first photo is the custom forged piston; on the left is the forged stock-style piston.
The piston main trusses have been moved inward to be more inline with the major thrust of the skirt to substantially reduce flex. At the same time, this acts as a heat conductor, allowing the piston to run much cooler. With the cooler running piston we are able to run a half point higher compression without the danger of running into detonation.