Legends of Combustion: GM LT5

What will become a recurring column on the blog is Legends of Combustion. An in-depth look at historically significant power plants from throughout the ages of automobiles. Today we're looking at the GM LT5:





Engineered by Mercury Marine using Lotus-designed 32-valve heads, the LT5 was a drastic change from every GM small-block that came before it. It featured an all-aluminum block based on the Gen-II LT engine with DOHC heads. Built by hand by Mercury Marine in Stillwater, OK, it produced 405 hp and 385 lb-ft of torque in its final year in 1995 from its 5.7L of displacement.

While the engine was eventually discontinued do to its high cost of manufacture and the much more powerful push-rod LS1, the lessons learned carried on into other GM products such as the venerable Northstar V8s found in Cadillac and Oldsmobiles.

If looked at simply by the numbers, the LT5 was an infant orphan that GM never gave a chance, and who could blame them when the LS-series engines were more powerful and cheaper to produce, but GMs first foray into a DOHC-V8 was a fair effort. Besides, the LT5 is actually good to look at, even if it's just as an end-table.