The Ford V-8 Engine Workshop
Boss 429 Mustangs were built for one reason; to qualify the engine for NASCAR racing.
Homologation rules required at least 500 cars with the Boss engine had to be sold to the public.
Racing versions were fitted to Torinos for NASCAR.
858 Mustangs were fitted with the engine in 1969, and only 499 in 1970.
"Fitted" isn't the right word. The engines were shoehorned
into the Mustang. The shock towers required major modification to
clear the heads and exhaust manifolds. This photo shows
the sculpting required as well as some reinforcing.
The battery was found in the trunk. This was done for
several reasons; to free up space in the engine compartment,
improve weight distribution, and improve traction on the
right side wheel. To keep explosive hydrogen gas and acid fumes
out of the trunk special filler caps with a vent tube were used.
Oil is supplied to the shaft mounted rocker arms through passages in the block and heads,
rather than through the pushrods as on the normal and CJ 429. Hydraulic lifters are used
on the street engine. When used in NASCAR racing, a mechanical cam is used. Oil to the tappets
is restricted by switching four special O-ring sealed plugs in the oil galleries.
|An even more wild version of this motor was built for the Can-Am racing series. The Can-Am 429 is an aluminum block monster displacing 494 cubic inches. Pistons run in dry steel sleeves.