[Christ]

Turbo chargers don't add that much backpressure to the exhaust stream.. Granted, it's measurable, but after installing a turbo, you can almost run a resonated straight pipe to exhaust the engine, therefore you lose the backpressure of a muffler, and it's not harshly loud in the lower ranges.

Anyway, good enough reasoning, but I was thinking something more like venting SOME of the pressure from the exhaust, like where air-pumps used to pipe into cat convertors... take that pipe, and use it's exhaust pressure to drive the sterling, instead of blocking the entire exhaust flow.

One could add several of those pipes to use the pressure instead of heat, and they could be mounted just about anywhere, since you'd be connecting them with pipes.

They'd be decreasingly efficient the longer those pipes were, and the further from the point of exhaust, but it might present another option to reclaim some energy.