During one of our never-ending technical discussions, Jim Grubbs at Jim Grubbs Motorsports (JGM) suggested that we take a look at the flow difference between 30- and 45-degree valve seats. While ...

Modern engines contain hundreds – nay – likely thousands of different parts. There are valves and springs, at least one camshaft, engines also have bearing inserts, an oil pump, numerous gaskets, ...

I bought a 1969 Chevrolet Chevelle SS 396 recently and want to know if unleaded gas will harm my engine. Also, will using regular unleaded instead of high-octane unleaded hurt? I’d rather use the less ...

The internal combustion engine lives by some pretty basic principles, some of which include letting air in, compressing said air, and letting air out. An engine's valves come into play during each of ...

As with most things in life, it’s the details that make the difference. You might not think that a measly degree here or there could make more horsepower when it comes to a valve job, but there’s ...