Battle of the Boost

Turbo vs. Blower: Which One Is Best?

- Johnny Hunkins

If it’s time to add more horsepower to your hot rod, and you’ve decided that boost is the best option, you might have pondered whether mechanical supercharging is the right move, or if a turbo-charger that runs off of exhaust heat energy is best. You’ve come to the right place, because in our decades of building project cars, talking to engine builders, and documenting thousands of amazing cars up close, we’ve seen and heard it all.

The answer, however, isn’t a straightforward one, because your own mechanical and fabrication skills and how you intend to use your car will matter in some significant ways. Before we break down the turbo versus blower debate, let’s first examine the options we’re leaving on the table, namely more cubic inches, more rpm, and chemical supercharging, aka nitrous oxide.

Q Other Power-Adder Options

Although adding boost to an existing engine is a time-honored way to add power, it can also be done without an external compressor. The first method here is to add more combustion events within a given time through an increase in engine rpm. An engine at full throttle can put out more power at 7,000 rpm than it can at 6,000 rpm, and if we do the math, we arrive at roughly a 16 percent increase. If instead of increasing the rpm we increase the displacement, we can arrive at the same number. A 350-cubic-inch small-block Chevy—when increased 16 percent in size to 406 cubic inches through a stroker kit—will also theoretically arrive at the same power output. Lastly, if we add 16 percent more oxygen in the form of nitrous oxide, the result will be similar. We’re leaving out a lot of asterisk details here, but we’ll assume you have a working familiarity with internal combustion engines.