Highlights

• This is an original 366 ci 585 hp NASCAR Baby Grand Firebird motor
• The 366 never reached the Grand National Circuit level
• The 400ci version was never an official option on a Pontiac but around 200 crated motors were sold for $2,000 per copy
• They feature 4 bolt main bearings, solid lifters, wide base forged Carrillo rods, an 800 cfm Holly 4barrel, and tunnel port heads (that placed pushrods at the ports center)
• Pontiac also made a dual and single quad 303ci version for SCCA TransAm Series Racing and a 400ci for the street
• The 400ci version has much in common with the SD 455 offered a few years later in the 1973 and 1974 Trans Am