My mate used to have a similar one on his 280Z, it was an "SK Sanyo" turbo kit.
It used the factory N/A exhaust manifold with a j pipe thing to bring the turbo up, turbo was an HT18 Hitachi turbo I think? This is going back quite a few years, he's still got some of the bits of it like the outlet pipe from the turbo, it had SK Sanyo cast into and a BOV/pressure relief valve.
The guy he bought the L20 off said it was supposed to be 200Hp, it was a factory non turbo L20. The turbo was so close to the battery it melted a hole in it when he took it on a really long drive then he ended up breaking almost all of the piston skirts a month or two later. I used the rods out of it for my 3.1L hah.