Ep 16. Roller versus Flat-Tappet Cams!

In this episode of Engine Masters, titled "Roller versus Flat-Tappet Cams!," the team tackles a common debate among engine builders - which type of camshaft is better, rollers or flat-tappets? Hosts Steve Dulcich and David Freiburger are joined by special guest Mike Mavrigian of Birchwood Automotive to test and compare the two types of camshafts to determine which one truly reigns supreme.

To start, the team explains the key differences between roller and flat-tappet camshafts. Roller camshafts have a smoother action, allowing for better valve control and more power at high RPMs. They also have improved durability and longevity compared to flat-tappet cams. However, they are more expensive and require a bit more work to install.

Flat-tappet camshafts, on the other hand, are simpler and more affordable, but tend to wear out faster and require more frequent replacement. They are also not as effective at high RPMs, making them better suited for lower performance engines.

To put these theories to the test, the Engine Masters team performs a series of tests on two identical engines - one equipped with a roller cam and the other with a flat-tappet cam. The engines are run on a dyno to measure power output and torque in various RPM ranges.

First, the team runs the engines with relatively mild cam profiles. Both engines perform similarly, but the roller cam engine produces slightly more power and torque in the mid-range RPMs. Next, they swap out the mild cams for more aggressive profiles and run the engines again. This time, the roller cam engine produces significantly more power and torque across the board, with a peak horsepower rating that is nearly 100 horsepower higher than the flat-tappet cam engine.

The team also tests the engines for wear and durability, measuring the amount of camshaft wear after various run times and oil change intervals. As expected, the roller camshaft shows virtually no wear even after dozens of runs, while the flat-tappet camshaft shows significant wear and even some chipping.

Overall, the Engine Masters team concludes that while flat-tappet camshafts may be suitable for lower performance engines, roller camshafts are the clear winner when it comes to maximum power output, durability, and longevity. However, they do acknowledge that the added cost and complexity of installing a roller camshaft may not be worth it for everyone, and that the best choice ultimately depends on the specific needs and goals of each individual engine builder.

Throughout the episode, the hosts provide detailed explanations of camshaft theory and technology, making this episode a must-watch for anyone interested in building high-performance engines. With its informative and entertaining approach, "Roller versus Flat-Tappet Cams!" is a standout episode of Engine Masters season 1.