Figured I'd add one last update, 2+ years later but figured I would post just for the sake of anyone else that cares about that sort of thing.
I took the twincharged setup off, it was neat but I had wicked boost creep and underhood heat issues, as anyone would expect cramming that much gear under a Volvo... I ended up going back to just a blower, overdriving it to the area of 18k blower speed rpm, putting in a ported 530 head, rsi stage 3 cam, valve springs, and converting to wasted spark with LS coils running a custom trigger wheel on the front crank. multiple water meth nozzles, and even running ice water in the intercooler tank on track days to keep the IATs from going insane. Almost 20psi from a roots is far past its efficiency point, but I was curious how far it would go. (I took apart the blower later, apart from some missing Teflon on the rotors it looked fine..)
Holy smokes, now it was making some power, 7000rpm redline, and fairly well calibrated butt dyno says 200hp with gobs of torque. sadly it started a chain of events that eventually killed my drive to keep refining the car. I twisted the keyways off 4 lower timing gears (fixed with a billet yoshifab one) I snapped the throttle shaft (fixed with a new linkage) blew up 2 m46s in one track day (within 6 hours of each other, including the swap lol) killed 3 power steering pumps (kept trying different coolers, I think a underdrive pulley would have fixed it) I did a t5 swap, got a few hours out of that, and then cylinder #1 melted a plug, and the debris actually caused a broken wrist pin and bent rod.
I made the call to part out the car, mostly because it had become one big living representation of "let's fix it tonight and drift it tomorrow" It was gross, hack, sloppy and not at all how I like to build stuff. As it was a track only car, I was spending $80 track fees plus fuel and other expenses to trailer it to the track and break it, just to spend all day working on it in the pits. In hindsight if you don't have a dyno keeping a car street legal is a very smart move if you are going to experiment with things. Live and learn.
All in all I have no ill feelings or regrets, it was fun to try, made great noises, and was a track favorite (other drivers said it was intimidating as heck to hear the blowing screaming up behind you!) I knew I was doing stuff the hard way, and handicapping my power potential (should have just had a 19t and called it a day haha) But it was a great learning tool, I got to get my feet wet in drifting, and met some very neat people along the way.
It looks like our local track is in trouble now, same old story of noise and general old grumps wanting it to go away, so I probably will stick to building street cars. One day I'd like a proper supercharged V8 Volvo, who knows...maybe one day I'll hear that screaming blower again, it sure is addictive! I hope anyone else that wants to try isn't turned off by my problems, tinkering for the sake of trying stuff without the fear of failure is something everyone should do!