The name Callaway is more often associated with the US company’s Corvette-based specials, but in the early 1980s, company founder Reeves Callaway set out to develop an engine for the Indy 500 in-house, with assistance from engine developer Hans Hermann. Designated the HH V8 in recognition of the German’s contribution, the engine never made it to competition as funding ran out.
However, the concept developed by Hermann was ahead of its time, packaging many engine ancillaries such as pumps on the front of the engine, in order to increase the space for underfloor aero. It also featured 1.5mm piston rings, very thin for the time and the titanium cam followers were hard chrome plated, another first.
Ultimately, the engine only ran a few times on the dyno, making around 680bhp, before the project was shelved. Fortunately, Callaway has dug the following video from its archives to give an insight into the motor’s development and the impressive (for the early 80s) capabilities of its operation.