Words and photos by Jeff Burk
3/8/06
know, I know, 1100 hp on pump gas engines are everywhere. You’ve heard and read about this type of motor in all of the magazines and in ads for engine builders, but bear with me just a little because I’ll bet you haven’t heard about a motor like the one I saw on Sonny Leonard’s dyno last month.
This is an engine that displaces 762 cubic inches. With a pair of split Dominators for carburetion the engine was dyno tested burning both 93 and 87 octane fuel from the local Exxon gas station and made over 1100 horsepower and 1100 ft-lbs of torque -- burning both fuels -- and never exceeded 6700 rpm on the SuperFlow dyno.
 The five-inch bore-spaced Donovan block is ready for the heads to be installed |
Sonny Leonard is justifiably famous for his IHRA mountain motor engines and recently the development of his Chevy-Hemi engines that have proved to be winners both in IHRA Pro Stock competition and NHRA Comp eliminator racing. The engine we are talking about here is not a version of his Hemi-Chevy, but, instead, is a brand new wedge-headed engine he has developed as the ultimate bracket racing engine and could, if the buyer wanted, actually be a street or marine engine.
Sonny had the Donovan folks cast a water-jacketed aluminum block specifically for this project. The block features five-inch bore spacing with the galley for the camshaft raised an inch.
 Here is the bare Sonny’s head |
 A close look at the combustion chamber |
 The exhaust port |