Also an odd bit in that the Keith Black 305 engine was offered to the Petty outfit, still in charge of all Chrysler racing distribution in 1971. Maurice, Richard and Lee decided NOT to use it, and rejected it because they had also elected to not run an "aero" package car in 1971. As told by Richard, we looked at the 305 and the 426 Hemi, then compared horsepower. On that basis, we rejected the 305, feeling that it could never overcome the raw horsepower factor of the output of the Hemi 426. (Richard Petty won the 1971 NASCAR championship, for which, Chrysler promptly rewarded him by pulling out all factory sponsorship in NASCAR!) In the Daytona 500 Richard won the race, with his driver, Buddy Baker in a Petty built and owned Dodge, placing second.
Of a V-8 engine in that era, ANY V-8 being able to turn up quickly, safely, and consistently into the 10K + range was just UNHEARD of! No one really took that into account. Dick Brooks AND Mario Rossi being the MOST surprised of all when the "lunch box" ran so well without any maintenance or engine issues! In the qualifying run that Brooks made, he was really, REALLY shaken in his belief about V-8 power in that were the big Hemi was done pulling, the lunch box had just begun to run. He liked it to an electric sewing machine that just keep on humming, higher, and higher.
Unfortunately, not much is known of the engine itself, nor where it went. Mario Rossi headed up DiGard racing for awhile, but Darrell Waltrip got him fired. He disappeared without a trace in the early 1980s and no one has seen or heard from or about Rossi since.