OS Giken is Japanese aftermarket royalty. The company has been producing performance parts such as clutches and limited-slip differentials in Okayama city since 1973. If you need some cool weekend entertainment, you can now watch one of the company’s greatest creations take shape in intricate detail.
About an hour long video was posted on YouTube channel inside japanese factories Shows the build of an engine for OS Giken’s S30 Z project car. At the helm of the L-series inline-six is OS Giken’s TC24-B1Z head, a modern reissue of the dual-overhead cam TC24-B1 head designed by company founder Masaharu Okazaki in the 1970s. According to one, only nine of them were originally made. Japanese language article Manufactured by the company. The part was brought back in 2017 as the B1Z with some updates to take advantage of advances in manufacturing over the past five decades.
Although the OS Giken factory houses a lot of modern technology, including CNC machines and CAD-equipped computers, which are essential in any modern manufacturing operation, it is not exactly the last word in highly automated efficiency. Like the Watanabe Wheel Factory, OS Giken is small-scale, with only a handful of employees working essentially by hand. The engine in particular is built the way a small race shop might.
If you have the time, this is a great step-by-step demonstration of assembling an engine. The build begins by thoroughly cleaning the original L-Series block and then filling it with brand new parts. The video walks you through every part of that process, from installation of the crankshaft, pistons and connecting rods, to porting and polishing the heads, to testing the finished product on the engine stand before installing it in the Z.
How This Japanese Workshop Builds Racing Engines from Scratch
Since there are no computerized wrenches tracking the torque applied to each bolt like in modern assembly plants, everything for this engine is done slowly and methodically. Before starting, the engine is started to make sure the oil is getting where it should, and two mechanics listen carefully for any abnormalities during the first few minutes of running.
The entire build took four months, perhaps partly because it is a side project from OS Giken’s main business of making individual parts. But listening to the inline-six song definitely made it worth the time.
