Crazy Diamond Performance Inc. (CDP), a Detroit-based company that specializes in alternative-fuel and performance powertrains, is developing a compressed natural gas (CNG) version of its 7.4-liter engine for vehicle applications through Class 6.
This family of engines, known as the Torquemaster, is designed around the General Motors LS platform. CDP's 6.9-liter Torquemaster (in a gasoline configuration) has produced more than 375 hp and 500 lb-ft. of torque in initial chassis testing. The 7.4-liter supercharged CNG engine is expected to deliver more than 650 lb-ft. of torque, the company says.
The engine's internals include a forged crankshaft, connecting rods and pistons, with a compression ratio of 10.2:1. The cylinder heads consist of lightweight stainless valves and hardened valve seats and are secured to the block with six torque-to-spec bolts per cylinder. The camshaft is a proprietary design that maximizes engine efficiency and performance in a low-boost CNG application. Engines are controlled by CDP's GEM engine management harness/system using an E-38 processor, designed to be EMD+ and/or OBD compatible.
CDP notes that it will begin testing the new 7.4-liter engine by the end of this year.
Last year, CDP announced that it was working on a patent-pending low-pressure direct-injection (LPDI) technology for engines running on CNG, propane autogas or other gaseous fuels.