From what I can understand, it's a 3.2L "kit" which that garage offers. It consists of a custom made crankshaft, pistons, connecting rods, pulleys, and is running a 4.375 R200 rear end with a Trust 5 speed Nissan Silvia transmission. Engine power is 392ps, and best time was that day of the video at 10.91. Carbs are 50mm Solex units, with custom made exhaust manifold and exhaust system. Prefers to use Solex over Webers due to ease of tuning. Pillow upper mount suspension, spring rates are 4kg/mm up front and 5kg/mm in the rear. Some custom work underneath and he's searching to get at least another tenth faster in the 1/4 mile.
Hope that helps you out, but my Japanese isn't fluent enough to catch everything.