Are those chinese turbos? The Chinese ones that went through the rotary world, turned out to be total garbage...
I wanted to add this, in regards to overlap, the most power I ever made with a rotary was running a port with huge overlap, a bridgeport is like runner cam with 300 deg at .50...Works great with a big turbine wheel.
I got the parts in for my next 2 rotor, its peripheral port turbo motor, in effect the intake and the exhaust never close. Its really interesting, the intakes are milled in, but the exhaust is bone stock, because Mazda incorporates an anti-reversion step in the exhaust port for turbo motors... Most rotary builders grind it out, not having the faintest of clues of why its there or what its for, but they see it as flow restriction so out it goes, and the power band gets cut down..
You've given me some inspiration though, when i am done moving house and shop at the end of summer, I am going to embark on a twin turbo D-150 build with a big block...