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Building an LS9 V8 at the GM Performance Build Center
When you think of brands like Aston Martin, Ferrari and AMG, the idea of their engines being built by
the hands of skilled craftsmen is no great surprise. However, most people would be very surprised to
learn that General Motors has its own special facility dedicated to building its highest performaning
engine by hand.
The GM Performance Build Center is located in a nondescript industrial park in in Wixom, MI, not far
from the company's Milford Proving Ground. The PBC is a 100,000-square foot factory that opened in
2005 and has since produced both the supercharged Northstar V8 that was used in the Cadillac STS-V
and XLR-V, as well as the dry-sump small-block V8 used in the Corvette Z06 and ZR1. The most recent
addition to the lineup is the dry-sump LS3 used in the new manual transmission Grand Sport. We were
invited by GM to tour the facility and even build one a monster LS9 that would eventually wind up in
someone's ZR1.
The Performance Build Center is a completely different animal when compared to GM's other engine
plants. The typical high volume engine plant consists of a long transfer line where bare engine blocks are
loaded on at one end and finished engines come off the other end. Along the way assemblers work at each
station adding parts to the engine. The assemblers typically spend the whole shift working at just a few
stations or even one station, putting the same part on engine after engine.
Things are done differently at PBC. Each engine is assembled by just one engine builder. The builder
starts off by preparing a set of pistons and then mounting a block onto an engine stand (above). Instead
of a transfer line where the engines move automatically from one station to the next, the stand is pushed
around the loop by the builder. The engine builders at PBC have all been recruited from the ranks of
skilled trademen at other GM plants.
Prior to the current downturn there were as many as 40 builders turning out up to 15,000 engines a year
from this Wixom facility. With the loss of the Cadillac engines and the slow down in Corvette sales, the
current production rate is about 5,000 engines per year, with 18 builders assembling the power-plants.
The plant has two main areas, the assembly hall and the test and inspection area.
The assembly hall has three loops and what is known as a kitting area. In the kitting area, bins of parts
needed for each station are compiled with exactly the right number of fasteners, gaskets, etc (above). If a
builder has any left over parts in the box at the end of a station, that means he has to go back and check
what he missed. One of the three assembly loops that was previously used for building Cadillac engines is
currently idle. Another loop is used to build the LS9 (ZR1) and LS7 (Z06) V8s while the third is used for
the LS7 and dry-sump LS3.
Mike Armstrong tutored and accompanied us as we began at the piston preparation area. The pistons,
rings and rods come into the plant pre-assembled from suppliers. The first step is to mark each piston,
rod and end cap with cylinder numbers and directions. We also check the rings to make sure the gaps are
on opposite sides. When connecting rods are manufactured, the caps are bolted on before the big-end
bores are machined. Those caps are removed before assembly and everything is arranged in the bin
before heading to the loop.
The first stage of actual assembly is the insertion of the camshaft. Before we put in any moving parts, we
take what looks like an over-sized Q-Tip, dip it in oil and swab the bores to ensure everything moves
smoothly (above). Once the cam is ensconced in the aluminum block, the 6-bolt main bearing caps are
removed so that the crankshaft can be installed. After popping in the main bearings and double checking
to make sure everything is facing the right direction, Mike lowers in the crank.