J code – A one-year offering of a slightly upgraded V-8 with 230 horsepower. They were both small blocks, but the cast-iron Cleveland is more durable. H code – This 250-horsepower Cleveland engine replaced the previous Windsor engine. G code – Offered for the Boss 302, this 290-hp engine blended the best of both the Windsor and Cleveland engines. It provided more displacement with 302 cubic inches and an upgrade to 210 ponies. From 1968 to 1973, the updated F-code engine replaced the previous 289 V-8. It was the V-8 engine but without the expensive, high-performance upgrades.ĭ code – The rare 210-horsepower 1964-and-a-half Mustang engines offered the four-barrel V-8 but lacked high-performance internals.į code – This Windsor V-8 was only used for the same 1964.5 model year. The 255-horsepower engine required premium fuel due to the higher compression.Ĭ code – The C engine was the base V-8 Windsor, 200-hp engine for 1965 to 1968. Here is a summary of the engine codes used for the first-generation Mustangs.Ī code – This was the upgrade from a basic V-8. Over the 10 years of production, Ford varied the engine options and occasionally re-used the engine code for a different model year. Fewer buyers opted for those engines, making them relatively rare. The more powerful engines had a higher price tag. Other options included a two-barrel carburetor V-8 a four-barrel V-8, and gnarly V-8 as options.

The base engine was typically a six-cylinder mill. In most production years, the Mustang was offered with at least four engine options. So you won’t necessarily know if that same original engine is still under the hood. Of course, things can change over the years. The VIN can tell you which engine was on board when the Mustang left the factory. The fifth digit of the ’66 Mustang’s VIN tells you about the engine provided.

How to check ford engine codes