New kid on the block

What if small block Chevy diehards had a “small” GM block that had all the benefits engineered into it that the best high-tech aftermarket racing blocks have to offer. What if there was a lightweight cast aluminum block that featured cross-bolted four-bolt mains and non-press fit sleeves, a block with enough clearance in the basic design that a crankshaft with enough stroke to build a 500-inch small block can be installed without any machining or grinding required to make room for it, a block with the camshaft galley moved up in the block also for clearance purposes.

This is what the engineering department at Racing Head Services (a division of Comp Cams) has done with a new aluminum GM LS series block that is now in production.

This front view of a production block shows the cam gallery and the timing chain case.

Developing this new block has been a project that has taken just two years from concept to development. Comp Cams VP of Engineering Brian Reese and his boss Scooter Brothers are the two guys mainly responsible for the new LS block that you are seeing here. We think it is one of the most exiting products we’ve seen for the GM small block racer in a very long time.

The venerable GM Chevy small block has been massaged in many ways over its more than 50-year history. In the pursuit of more performance the cast iron GM blocks have been given four-bolt main bearing caps. Racers have ground on and machined the original to make it lighter and clearanced it to accept a stroker crankshaft. Deck plates have been added to allow more stroke and engines over 450 cubic inches. GM themselves have improved the block over the years developed the SB2 block and cylinder heads. The aftermarket manufacturers have tooled up to make both cast and billet versions of the Chevy small block.