TOPIC: Mercury ZR-1

I like to watch the car auctions on TV. The other day they were talking about the motor in a 1990 ZR-1 Corvette. I learned that the legendary ZR-1's LT5 motor was built by Mercury Marine.

From Popular Mechanics www.popularmechanics.com/cars/news/4237615

The engine that resulted from that Corvette/Lotus collaboration was called the LT5. It was an all-aluminum-block V-8 with the same displacement, 5.7 liters or 350 cu. in., and the same bore centers (4.4 in.) as the normal Corvette's L98 pushrod engine. It had an unusual low-rpm/high-rpm intake tract (fort the time) on top of the engine, with solenoids that closed eight of the 16 intake runners and shut off the fuel injectors anytime the engine operated at less than at full-throttle. At full-throttle, all 16 intake runners and fuel injectors were open for business. A valet key in the instrument panel kept the engine in the low-power mode, making only about 250 hp. The LT5, intended to run at much higher rpm than the pushrod engine, was rated at 375 hp at 6000 rpm. It was among the most potent V-8 engines in the world at the time and just 5 hp shy of the Ferrari Testarossa. By comparison, the normal L98 Corvette engine was rated at only 250 hp at 4400 rpm. In 1989, Chevrolet built a few Corvettes with the LT-5 engine as a test fleet. Once they were satisfied with the engine's performance, drivability and durability, the Corvette team had to find a way to build the engines here in the U.S., instead of Lotus doing the job in England. Mercury Marine, which had by that time built thousands of GM small-block V8s for pleasure boats, was selected to build the LT-5 engine at the Mercury plant in Stillwater, Okla.

I believe that Mercury got the contract because they had the technology to work with and machine aluminum castings.

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A lot more to that than meets the eye.

Very cool stuff guys, thanks for sharing. I read somewhere (BoatTests.com maybe ?) that GM is still producing the big block 454 motors EXCLUSIVELY for Mercruiser applications, as that size motor is not used in any automotive applications any longer!? Gotta hand it to the folks on "the dark side", must have some ole 'motor heads' still on the staff.

Cool eh? They actually put one in a boat that looked like a Corvette, and ran it for a bit. pretty neat stuff.

Mercs aluminum machining ability was also a factor, not mentioned in the PM article. I could not find an article from Merc.

In 1997-99 Chevy commissioned Malibu Ski Boats to build 50 Corvette ski boats with the 505hp LS7 engine. Coming up on the 20 year old mark for these. www.waterskimag.com/ski-boats/2009/12/04/malibu-boats-corvette/

MTI (Marine Technology Incorporated) also built a Corvette inspired boat powered by twin 1350hp Merc V-8's. It's for sale asking only $1.7 million. www.gtspirit.com/2011/10/08/for-sale-2700-hp-corvette-boat/

50 boats? Did not realize the built so many. Wonder where they ended up?