Looks like he's gone from Home Depot motorsports to Muffler Shop engineering; that 'hot side' charge air pipe is just an el cheapo 90 degree exhaust pipe, complete with flow impeding wripples at the inside of the bend. He still uses ABS on the 'cool side' return pipe. I'm really glad someone is willing to put forth the effort on the OM617 engines, but good IC design requires the least restrictive plumbing possible, especially when you've got lots of complicated bends and awkward angles. Most of the pro tuners use either mandrel bent aluminum or stainless steel IC plumbing. I've got some mild steel bends set aside for my OM603 IC project, but at least they're mandrel bent for smooth transitions.

Wonder if he's bothered to turn up the injection pump's fuel quantity, or if this IC is like the others, and just for show.

BTW: I'll bet if he were to use the intake manifold from an older W115 chassis OM617 engine, he wouldn't need to do all those welding mods.