A 400M Takes On A 408 Cleveland In A Blue Oval Dyno Battle

Dyno-testing engine combinations provides builders with hard data, but it can also reveal the answer to some curiosities. You might imagine that two Ford pushrod engines with similar displacements might deliver similar outputs. To find out, A 400 Ford vs 408 Cleveland battle took center stage at Titus Performance.

Two decades ago, Mark McKeown, of Titus Performance, brought a 400 Ford, also known as a 400M to the Engine Masters challenge because it fit the strict rules perfectly. Recently, a 408-cubic-inch version sat on the shop test stand. Featuring a small-port two-barrel intake manifold, the setup runs a custom camshaft. This build targets a street-driven truck requiring a broad torque curve to haul heavy loads efficiently.

Putting a big-port, 408-cube Cleveland against the small-port engine revealed a stark contrast. Both engines feature a 4-inch stroke, identical compression ratios, and matched test accessories. Interestingly, the 400 Ford utilizes a slightly larger camshaft.

“Now, it has been said all over the, you know, for years and years and years that it’s been the big myth that Cleveland’s with the big ports, you got to zing them on 10,000 RPM, they don’t make any power down low, they don’t have any torque,” McKeown said.

Proving that theory wrong, the big-port engine maintained more than 500 lb-ft of torque across a massive 3,000 rpm range. Testing aftermarket port stuffers on the block showed zero performance change.

“The stuffers meant absolutely nothing as far as gaining torque, losing torque, changing the RPM band,” McKeown said.

Meanwhile, the small-port engine peaked at 473 horsepower. Falling off earlier in the rev range, it produced a massive 81-horsepower deficit compared to the other layout.

“Horsepower is a function of torque versus RPM. So that is sort of the secret of making big power,” McKeown explained. “You have to make torque, you have to make good torque and carry it and then carry it out through the RPM.”

It is always interesting to watch dyno experiments like this, especially when they challenge long-held truisms. There might not be a replacment for displacement, but when all things are equal, airflow rules the day.