Dumb question of the day

What does "Flat Head" refer to? It's a straight 4 cylinder, but I've no idea what that term is used for.

In a flat head engine, the valves are in the block beside the cylinder, instead of in the cylinder head above the piston. The combustion chamber is kind of oblong shaped to cover the top of the individual cylinder and extend out over the top of the associated valves. From the outside, the top of the cylinder head is more or less flat, with the spark plugs sticking directly out the top. In a flathead engine, the manifolds are mounted to the block, in an overhead valve engine the manifolds are mounted to the cylinder head, since that"s where the valves are located.

In the flathead engines I"ve seen, the valve lifters ride directly on the camshaft & push directly on the bottom of the valve stems. No pushrods, rocker arms, etc.

Most automative engines were flatheads up until the 50"s & early 60"s. I"m assuming it was because they were cheaper to produce, as they certainly didn"t have any performance advantage over a overhead valve engine.

Kind of suprised me that tractors from the 1920"s had overhead valve engines when most of the autos were using flatheads.

Keith

Perhaps he was thinking of the Cub which used a flathead engine for many years...

Either way, as already stated, the H is overhead valve (OHV).

The men that ran moonshine years ago used those Fords with the flathead engines and when they weren't doing that they raced one another on dirt tracks. That was probably the start of NASCAR.

We did have a 500hp Ford engine with overhead valves that was used in Tanks and the M7 Mobile Field Dynamometer that the Army had at Aberdeen Proving Ground. The M7 used 2 of these engines for power. The engines were made in the 40's. Hal

The flathead was the "older" design that most manufacturers left behind in the 30s except for Ford and Chrysler (switched in the 50s) and the smaller engines used on lawnmowers. The flat head is limited in its power potential. The best example is the Ford flathead V8 was out powered by the standard Chevy inline 6 through most of the 40s and into the early 50s.

Today even lawnmower engines are using OHV designs to get more power.

Really, I ask questions here because people tell me things specific to old Farmalls that a Google search may not bring to light.

So, your pissy little comment is really unnecessary.

Like others have said, flat head means no valves in the head. Also sometimes called an "L-head" engine if I"m not mistaken for the shape of the combustion chamber when looked at from the crankshaft end of the engine with X-ray goggles. With the piston at the bottom, it looks like an upside-down, fat L.

The old Briggs & Strattons (non-OHV) are flatheads. Flathead heads are not really flat on the outside, obviously, but they are flat-er than an overhead valve engine.

Ya have to weed these types out in your own mind and just remember to disregard anything that fellow ever tells you in the future. :>)

Allan

I thought you had an H? An H is NOT a flathead. It is an overhead valve engine.