Building The Original Corvette ZR-1 Engine Was Serious Business

Building the first and only four-cam, 32-valve V8 to grace a Corvette required lots of attention to detail.

Chevrolet

When the original Corvette ZR-1 made its debut back in 1989, the big story was its engine. Designed by Lotus, the ZR-1's all-aluminum 5.7-liter V8, dubbed LT5, was the first and only Corvette with dual-overhead cams and four valves per cylinder, and was good for 380 hp in its day. Interestingly, Chevy itself didn't build this engine, instead farming out production to Mercury Marine's MerCruiser division.

Advertisement - Continue Reading Below

MotorWeek visited MerCruiser's Oklahoma facility to get an inside look at how the LT5 was built in 1992, shining light on this fascinating engine. Chevrolet chose MerCruiser partly because of its experience in working with aluminum, which was put to good use for the LT5. Using automated machines, around 95 percent of the LT5's drilling, boring and machining was completed at MerCruiser.

All the tolerances of the LT5 were checked using automated machines too, since they were required to be within seven microns of Chevy's specs. Much of the final assembly was completed by hand, though, and each engine was put on the dyno for testing before being sent off to Chevy.

MerCruiser's attention to detail was totally befitting of an engine like the LT5, which remains a legend to this day. An engine so great, Chevy brought its name back for the new ZR1.


Advertisement - Continue Reading Below
More From Vintage