Not everyone has had the pleasure of being in an assembly room while an engine is going through its various stages of construction. Between the liability of having observers and the distraction potential, along with the limited workspace, the behind the scenes work is usually “behind the scenes” for good reason. However, Head Asssembler Adam Golen, of Golen Engine Service decided to bring viewers with him via GoPro as he machined and assembled a 370 cubic-inch LQ9 shortblock for Diablo Formula Racing.
“The customer plans on running a 80mm turbo with 15 psi of boost,” says the owner of Golen Engine Service, Chad Golen. “So we decided on an LQ9 block for overall strength.” Once an iron LQ9 block was acquired, Golen went to work to set all the specs exactly as he wanted them, to have a perfect base on which to build.
“We bored and performance-honed the block with a torque plate to 4.030 inches,” Golen says. “We zero-decked it, align-honed the mains, added ARP main studs and installed Durabond Performance cam bearings.” Golen then took the factory LQ9 crankshaft, tossed the factory reluctor wheel, and swapped in a billet 24X unit, and dynamically balanced the assembly.
To prepare for the 15 pounds of boost the customer called for, Golen chose to go with Callies CompStar H-beam rods, with upgraded ARP 2000 rod bolts, for the ultimate in affordable reliability under the stress of boost. Again, in the name of reliability, Clevite H-series bearings were chosen for the rods and mains, and a Melling high-volume oil pump was sourced to provide adequate amounts of lifeblood to the engine.
On the end of those rods, Golen opted for a set of boost-ready Wiseco forged pistons. In addition to being a strong forging, Golen opted to use heavy-duty tool-steel wrist pins in the assembly, along with ArmorGlide dry-film skirt coating to help reduce friction in the bore. For the piston rings, Wiseco stainless steel units were chosen. “We gapped the rings and set all the clearances with the amount of boost that was going to be run in mind,” Golen explains.
Designed as a street/strip build, a hydraulic roller camshaft was chosen, which limits the overall RPM of the engine. “7,000 rpm would be about the max engine speed for this combo,” reveals Golen. “900 horsepower is probably a safe power limit for these parts.”
While the whole assembly process is shortened into eight minutes and thirty-eight seconds, thanks to the magic of time lapse video, the actual process is nowhere near as fast, due to all the different factors that come into play during a professional rebuild. You’ll notice the constant measuring and recording of measurements, along with the tedious organization.
This video gives you a fun, quick look inside the process and just how much work goes into putting together a 900-horsepower-capable shortblock, from initial machining to the final coat of paint on the shortblock.