When you think of the Ford Mustang, generally you think of some loud and brash V8-powered monster, correct? Well the fact of the matter is that a great majority of Mustangs sold in America were powered by less-than-awesome engines like the Cologne 4.0 or the Pinto 2.3 liter 4-banger. Even the very first Mustang was sold en masse with a 200 or 260 cubic-inch inline-six cylinder engine.

Today finding a restored Mustang with its original I6 engine can be pretty challenging, and these engines probably don’t get the respect they deserve. Over on the YouTube though the Costa Mesa R&D Automotive Machine Shop posted this video of a classic Mustang I6 clacking away on the SimTester. It’s kind of cool to watch these engines operating in slow motion.

A SimTester, for those who haven’t figured it out yet, is sort of like a “dry run” for an engine. It turns all the major mechanical components on an engine without fuel or spark. This allows engine builders to ensure that everything is working-as-intended before firing the engine up for real.

The benefits of a SimTester are obvious; if there’s a loose screw or a broken component, it is a lot easier to shut down an engine at these low speeds. It also gives us a look at the overhead valve setup clacking away, and the cameraman even sticks his fingers into the exhaust ports to demonstrate how much compression is in each cylinder.

Having a SimTester to use would be mighty welcome in our own garage, though it’s definitely more of a machine shop-type device.