Check out the “Godfather”...
Check out the “Godfather” versus a standard GM big-block; the crank centerline stands at 12.225 inches from the deck while the big-block checks in at 9.80. It’s also about 8 inches wider at the top of the valve covers and the cam bore is raised nearly 2 inches to make room for the crank’s massive throw. Options include water jackets, stock big-block water pump mounts, and side engine-mount lugs. Shown here is the full-race block with no water jacket.
Lift numbers like that require...
Lift numbers like that require a stronger cam core. Here’s a closer look at the drastic difference in base circle versus a standard big-block cam (left). The practically rectangular lobes are ground on a 121-degree lobe-separation angle with a 118-degree centerline. The intake is advanced 3 degrees.
You can’t use standard GM...
You can’t use standard GM paired guide bar roller lifters with their wee little 0.842-inch body to transmit 1-inch-plus lift, so Leonard relies upon burly keyed Cam Effects or Jesel roller lifters with 0.950-inch wheels in a 1.095-inch body that could practically double as small casters.
Coming in just a bit under...
Coming in just a bit under 6 inches, the 5.875-inch stroke of the Godfather’s billet steel crank (left) is comically larger than a common 4.25-inch-stroke 454 unit (right).
The valves will never see...
The valves will never see all that lift if the pushrods buckle under pressure, so rather than ⅜-inch pushrods, the Godfather uses ⅝-inch pushrods—11.300 inch on the intake, and 12.735 inch on the exhaust.
Every part of the Godfather’s...
Every part of the Godfather’s crank (right) grew except the bearing surfaces; it still uses big-block Chevy main and rod bearings.
Most 540ci big-block strokers...
Most 540ci big-block strokers use a 6.385-inch rod (bottom). To create 1,005 cubes, the Godfather requires rods in the 8-inch range. The GRP aluminum rod shown here is only for full-race versions; the aforementioned street versions will get billet steel rods.
Pondering how much work it...
Pondering how much work it would take to get one in a muscle car? If you’re up to the challenge, Leonard’s got you covered. Godfather number two was actually built as a slightly less radical pump-gas version intended to go in a street car down in Australia. That one “only” makes 1,650 hp at 7,000 rpm, and 1,400 lb-ft at 5,700. Why? “For the bragging rights,” was the response.
Redefining the concept of...
Redefining the concept of “big bore,” the Godfather’s piston measures 5.220 inches in diameter. For comparison, the bore on a standard 454 big-blocks measures 4.251 inches.
The fabricated sheetmetal...
The fabricated sheetmetal intake mounts four 2.750-inch (id) two-barrel Accufab throttle-bodies that flow 924 cfm each for a total of 7,392 cfm from all eight. Eight 65-lb/hr main injectors and eight 35-lb/hr supplemental injectors are used to fuel the Godfather. The supplemental injectors only come on under WOT.
By The Numbers
1,005ci Big-Block Chevy
||Sonny’s Automotive Racing (SAR) billet with 2-inch raised cam
||Sonny Bryant billet crankshaft
||GRP billet aluminum
||SAR custom pistons
||ATI Super Damper
||custom Dailey Engineering
||custom Dailey Engineering 7-stage
lightweight dry-sump system
||Sonny Leonard CNC-ported Special Edition hemispherical heads
||SAR/T&D/Jesel shaft-mounted rocker system
||SAR sheetmetal Pro Stock intake with SAR/Accufab throttle bodies
||custom 70mm camshaft with 121 LSA, 1.300-/1.315-inch valve lift and 290/319 degrees duration at .050
||keyed Cam Effects roller lifters with 0.950-inch wheels in a 1.095-inch body
||⅝-inch diameter; 11.300-inch intake, 12.735-inch exhaust
||custom MSD beltdrive
||Sonny’s billet valve covers