Subaru Supercharged?, Thinking out loud, what are the obvious reasons not to? Options

[jsteele22]

BTW, The Subaru EG33 (6 cylinders, from the SVX) takes the same sized pistons as the EJ22, so there are commonly available low-compression pistons. And I recall that someone was "working on" a supercharging kit for that engine. That might make for a fun little project...

[Boojum]

The one thing that you absolutely must do is find a method to make far more power than you're losing. <b>Some early turbo cars used a series of swing valves to redirect ehaust and intake around the turbo when it wasn't spooled. </b>I'm doing an exhuberant n.a. component on my car, but the air will pass through the chassis without stopping at certain speed/rpms. And I haven't thought too much about a supercharger. Maybe a clutch on the drive pulley and a valve to redirect air to a n.a. scoop at 60mph?

Yeah, alpha, it's a funny thing you mention this. I think Saab re-invented this back in the late 70s, but the idea was actually first used on the Chrysler turbine car! It had vanes that could redirect gasses to the power turbine that would be used to reduce the amount of time it would take to spool the turbine, and even turn the gasses around to provide an "engine braking" effect like piston engines, because they wanted the car to be familiar to a piston driven car.

But it's a funny thing you mention it because the new Porsche 911 turbo uses vanes on to also reduce the apparence of lag, and eliminate the need for a wastegate. I think the VW TDIs with the red "I" in North America also have variable vane turbos, as well do many large diesel tractors. It's more efficient than the wastegate, and it delivers boost across a wider RPM band. Cool stuff.

edit: wanted to put this cool gif animation of a VVT turbo up, for everyone to really see what goes on:
(IMG:http://pics.tdiclub.com/data/503/27019turbo_jpg.gif)