GMC PM251 Cylinder Heads

Step back in time with our modern reproduction of the iconic Chevy 461 double hump cylinder heads, now cast in lightweight aluminum! In this video, Joe and Wyatt discuss the features that bring the vaunted camel hump heads into the 21st Century.

Need help selecting the best cylinder head gaskets for your engine? Click here to learn the differences between copper, steel shim and MLS head gaskets. Plus install tips!

Learn how to re-build a junkyard Small Block Chevy. A step-by-step guide on how to select a SBC, machine the valve guide bosses down, and what parts to use to upgrade to your personal liking.

Engine Cylinder Numbers

Whether you’re looking for performance improvements or heat reduction, if you decide to wrap your headers, we'll show you the benefits and possible precautions to take before you wrap your exhaust.

Speedway Motors employee Tim M. has been chipping away steadily at his '29 roadster for awhile now. This time Tim tackles one of the big pieces, the long block rebuild of his 241 Red Ram Hemi.

In this budget build, a GM rear end is upgraded in order to hold 400+ HP. See how spherical bushings are replaced in a used 8.5” GM 10 bolt rear end.

Tim M. continues his quest to breathe life into a tired old 241 Dodge baby Hemi. This round, Tim dives into giving the 241 an electrifying makeover, courtesy of a Pertonix electronic ignition system, all cleverly hidden inside existing hardware.