The term “crate engine” is somewhat of misnomer these days, especially when working with custom engine shops. They may advertise a variety of crate engines — both for race and street — but if a customer is going to spend over $40,000, then he can make a few changes to the final build.
Needless to say, the owner of this 1,000-horsepower supercharged 461ci LSX engine shown in the video made a bunch of changes.
“He started with the idea of a 800-horsepower naturally aspirated engine,” recounts Mark Davis of Precision Race Engines in McMinnville, Tennessee, noting that the final destination for this engine is a custom tube-framed ’72 Chevy pickup. “About a quarter of the way through he wanted more power but still wanted to drive it on the street. That’s when we went with the Whipple.”
The foundation is a Chevrolet Performance LSX tall-deck block bored out to 4.155 inches. Balanced internals include a Callies steel crank with 4.250-inch stroke, Callies I-beam 6.125-inch rods, RaceTec forged pistons (9.2:1 CR), Total Seal rings and Clevite bearings. A Comp Cams LSR 309/325 hydraulic roller cam is used along with Smith Bros. pushrods and JP Performance double-roller timing set.
Precision chose the Brodix STS BR7 273 cylinder heads for this project. These heads flow more than 415cfm through 273cc intake ports and come out of the box with matched ports, 71cc combustion chambers, blended bowls and 2.250/1.614 valves. Finishing up the heads are Manley valve springs and Crower shaft-mounted rockers.
Rounding out the long-block assembly are Moroso 7-quart pan, Melling oil pump, Moroso pickup, ARP hardware, Victor gaskets, ATI balancer and Chevrolet Performance water pump, head gaskets, timing cover and valve covers.
“With the tall deck we had to use RHS intake spacers,” says Davis. “The biggest challenge was getting all the accessories to fit. The first system put the drive pulley out front of the balancer. Then we went to the Billet Specialties drive that runs right off the balancer. That tightened up the package and gave us more room for all the accessories.”
After breaking in the engine on Brad Penn oil, Precision planned three test sessions on its Stutska dyno. The first two were on 93-octane pump gas. At 8.5 pounds of boost, the engine pulled 903 horsepower with 769 lb-ft peak torque. At 10 pounds, the number rose to 951 and 825, respectively. With race gas and 12 pounds of boost, the engine pulled 1,021 horsepower with 855 lb-ft torque.
“I’m sure we could get even more power out of it, but the customer wants to drive it regularly, so we need to keep it calm for the street and make it last,” sums up Davis.