05-07-2012, 03:39 PM
Inside Bruce Crower’s Six-Stroke Engine
Inside Bruce Crower’s.pdf (Size: 60.63 KB / Downloads: 61)
Bruce Crower has lived, breathed and built hot engines his whole life. Now he’s working on
a cool one—one that harnesses normally-wasted heat energy by creating steam inside the
combustion chamber, and using it to boost the engine’s power output and also to control its
temperature.
“I’ve been trying to think how to capture radiator losses for over 30 years,” explains the
veteran camshaft grinder and race engine builder. “One morning about 18 months ago I
woke up, like from a dream, and I knew immediately that I had the answer.”
Hurrying to his comprehensively-equipped home workshop in the rural hills outside San
Diego, he began drawing and machining parts, and installing them in a highly modified,
single-cylinder industrial powerplant, a 12-hp diesel he converted to use gasoline. He bolted
that to a test frame, poured equal amounts of fuel and water into twin tanks, and pulled the
starter-rope.
“My first reaction was, ‘Gulp! It runs!’” the 75-year-old inventor remembers. “And then this
‘snow’ started falling on me. I thought, ‘What hath God wrought…’”
The “snow” was flakes of white paint blasted from the ceiling by the powerful pulses of
exhaust gas and steam emitted from the open exhaust stack, which pointed straight up.
Over the following year Crower undertook a methodical development program, in particular
trying out numerous variations in camshaft profiles and timing as he narrowed the operating
parameters of his patented six-stroke cycle.
Bruce’s Background
“You’ve kinda got to be in the cam business and know the dynamics of engines,” Bruce
Crower says about how the idea occurred to him. And he certainly has that background.
He was building and racing hot rods (and hot bikes), manufacturing speed equipment and
operating his own speed shop in his home town of Phoenix when he was still a teen.
After moving to San Diego in the 1950s, among other exploits he dropped a Hemi into a
Hudson and drove it to a 157-mph speed record at Bonneville.
Inevitably, the inventive and inexhaustible Crower built up a major equipment business in
superchargers, intake manifolds, clutches and, especially, camshafts. He’s also credited
with first suggesting a rear wing to Don Garlits—in 1963, three years before Jim Hall’s
winged Chaparral. Bruce Crower is now in Florida’s Drag Racing Hall of Fame.
Crower actually had introduced a wing two years earlier, during practice on Jim Rathmann's
1961 Indianapolis car—five years before Jim Hall’s winged Chaparral.