there is a reason why GM installed same long ago in buses and heavy trucks. Although both were in low rpm diesel applications, the tremendous boost it gave at low rpms allowed what seemingly was too small of an engine to push some mighty big loads.
The dude that wrote that above is incorrect.
GM installed blowers on 2 stroke engines because they can't run without them. RJP has it right.
I've worked on Detroit and EMD diesels forever... they don't have intake valves, they have ports that are uncovered when the piston is at the bottom of it's stroke. When the piston is at the bottom the 4 exhaust valves are opened and the blower pushes the exhaust out and the fresh air in.
On a slightly related note, what would be a fun project on a gas engine....
Detroit v92 series use both a blower and turbocharger. The blower is for the engine at low rpms, when the engine speed and load increases it disengages the blower and just uses the turbo charger. Would be cool to find a way to adapt that clutch and system to a car. EMD 710's do this as well if I recall, tho the blower probably weights more than your car engine.
The blowers on the 645's I work with (btw if you like blower whine, these two engines humming along at 800rpms is awesome)