Interesting images. Are we sure that those are turboprop engines? The three-bladed prop and cowling configuration are reminiscent of a four- or six-banger piston engine if you ask me. It could be the exhaust for that sticking out the side of the cowling. Perhaps a partially liquid cooled engine would account for the large inlet and exhaust duct on top and rear end, or a turbo-charged one with a large intercooler.