I've seen SOME success with them. One is a Chevy truck (late 90's, IIRC) that put down some 9 second ETs with the STS setup.
Having been around turbocharging and knowing how they work, I would be inclined to say that the old tried and true method of mounting them in the engine compartment would generate better success. I just can't see using pumps and scavenge pumps to get cool, clean oil to the turbo itself, and then using 20+ feet of charge piping. With that much charge pipe, it would be one laggy POS. I swapped in a Isuzu NPR IC into my old SVO and right away I noticed more lag due to more tubing. It takes longer to "pack the pipes" with charge air. Also, you still need to mod the engine. Just adding a rear mounted turbo is still doing the same thing as mounting one on the manifold....you are packing the motor full of compressed air, which means you'll have to upgrade the fuel system as needed. Just bolting on a turbo itself usually is a headache waiting to happen....speaking from experience (I had a '74 Maverick/302/c4 and I did my own rendition of a home-made turbo).
But, if you can live with lag time of 1 minute or so and lots of pipes, pumps, and other associated parts, it looks like the STS would work.
"it is better to appear ignorant than to open your mouth and remove all doubt"--Mark Twain
<font size=-1>[ This Message was edited by: mavman on 6/17/06 6:51am ]</font>