How to Tell Which 351 CID Engine Is in a 1977 Ford Truck?

Ford trucks in the 1977 model year were available with a variety of engines, ranging from a 4.9-liter, 300-cubic-inch, inline-six cylinder to a 7.5-liter, 460-cubic-inch V-8. An interesting result of the many engine options was the use of two 5.8-liter, 351-cubic-inch V-8 engines. The 351 Windsor was named for the Windsor engine family that includes the 260, 289 and 302 cubic-inch V-8's. The other 351 cubic-inch engine is the 351 Modified, which is a member of the Ford 335-series family that includes the 351 Cleveland and 400 cubic-inch V-8's. There are several ways to positively identify which 351 engine you have.

Instructions

1

Park the vehicle on a level surface and set the parking brake. Open the hood and follow the upper radiator hose from the radiator to the engine. If the hose attaches to the intake manifold, it is a 351 Windsor. If it attaches to the engine block, it is a 351 Modified.

2

Examine the valve cover. Count the number of bolts on the cover. The 351W has six bolts. The 351M has eight bolts. Also, the tops of the 351W valve covers are flat. The 351M valve covers have a peak toward the front.

3

Examine the fuel pump. The mounting bolts on the 351W are horizontal to each other. The bolts on the 351M are vertical.