Complex sentence: The engine was available only in 1971 production Boss 351 Mustang's, it has four-bolt main block/caps and premium crankshaft, as both are constructed from high-strength nodular iron.
Split into simpler sentences: The engine was available only in 1971 production Boss 351 Mustang's. It has four-bolt main block/caps and a premium crankshaft, as both are constructed from high-strength nodular iron.