The Boss 429 engine was designed and used in 1969 and 1970 Mustangs. Ford had to produce at least 500 Mustangs to qualify for the NASCAR Grand National Racing. Virtually all of the parts on a Boss 429 are unique. Here are some of the characteristics:
- The spark plug holes are in the center of the cylinder heads.
- Boss 429 heads require a very rare, one of a kind, valve cover.
- Boss 429 had two different length rocker arms.
- Boss 429 heads had crescent shaped combustion chambers.
- The exhaust manifold was unique.
- There was a special oil filter and fittings for an optional drag pack external oil cooler.
- The air cleaner had an extra long snorkel to bridge the very wide intake and cylinder heads.
- Used a Carter fuel pump, part number C9AZ-9350A.
- Used a Rev. Limiter, located on the left hand fender apron. The Rev. Limiter was set at 6150 RPM.
- The Autolite battery was relocated to the trunk on the passenger side to better distribute the weight.
- The spare tire was moved to the driver’s side.
- The Boss 429 required a Big Block FoMoCo radiator, part number C8ZZ-8005-C.
