Corvette ZR1 High Tech LS9 - First Look: Building The ZR1's 638HP Engine

We Head Inside The Wixom Performance Build Center To See What's Involved In Assembling The New Supercharged Ls9.

Sucp_0811_05_z Corvette_zr1_high_tech_ls9 Camshaft_bath 2/30

Before being installed, the camshaft is given a liberal bath in Mobil 1 oil. also, notice the custom installation tools that keep the cam (211/230 @ .050 and .562/.558 lift) from nicking the cam bearings. Think they got this idea from corn on the cob?

Unlike the lS7, which has a cast crank, the lS9 wields a forged steel micro-alloy crankshaft. it's easy to identify since it has nine flywheel boltholes in the back compared to six on the lS7 crank. GM engineers believe more is better due to the increased output of the engine.

Here you can see one of the eight new oil squirters that arrive mounted in the block. These squirters keep chamber temperatures down and reduce drivetrain noise. This is the first time that General Motors has used oil squirters in a small-block application.

The build process relies heavily on computers, but the builders still use old school methods. One of these is marking all of their main caps with orange paint, even though they're stamped at the factory.

Sucp_0811_10_z Corvette_zr1_high_tech_ls9 Titanium_engine_rods 6/30

The use of exotic titanium in the engine rods will continue, but gM has moved to forged 9.1:1 compression pistons. The floating pin pistons are anodized on the top and the skirts are polymer coated. The engines are assembled by the builder at a series of 11 stations. at each station, the parts needed for that station are provided in kitting trays like this one. lS9 parts are placed in green bins and racks so they won't be confused with lS7 parts.

This tool is specific to the LS9 assembly and helps guide the rod into the engine. in addition to making sure no damage is done to the crank, its main job is to ensure the rod doesn't damage the oil squirter. Custom tools like this are located all along the line to guarantee high build quality.

Each station is laid out to accomplish a specific task. Only the tools and parts needed for that station are on hand. The task sheets are colorcoded green for lS9 and white for lS7 engines. Note the white template that shows the order in which the bolts need to be torqued. Most of the builders know the pattern by now, but they are there for reference. The white plastic tray on the left side of the workbench is where lS7 parts are "kitted."

The biggest difference between how you assemble an engine and how gM does it is in the use of specialized tools. This alignment tool makes sure the timing cover is dead center to the crank. The top plate ensures that the bottom of the cover is flush to the block. This is critical to ensure a leakfree seal to the oil pan.




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