" From: Tom Jennings <tomj@xxxxxxx> " " " http://wps.com/AMC/Navarro-Indy-motor/images/indy-side-bad-photo.jpg " " There's two waste gates, so I guess the exhausts are in parallel? i don't think that necessarily follows, though it does rather look as though the turbines -aren't- plumbed one into the other. if you want to control the boost of each stage separately [to equalize the workload], you need a wastegate on each turbine. sudden thought: they're popoff valves, not wastegates. " The compressor side must be in series. probably. i don't see the point otherwise. " http://wps.com/AMC/Navarro-Indy-motor/images/indy12.jpg " " It's a hell of a tangle in there. What a pain to assemble. hard to tell what connects to which! ________________________________________________________________________ Andrew Hay the genius nature internet rambler is to see what all have seen adh@xxxxxxxxxxxxxxxxx and think what none thought