Jim "Yeah, I'm an engineer" Crider wrote:
> This is
> particularly true for turbocharged engines (like the Audis,
Cadillacs,
> Bentleys),
Here's another bit of info re:turbo engines and extra fuel in the
exhaust. When you're overrunning the engine, the turbo has an
unfortunate tendency to slow down. Blowoff valves can help remedy
this. So can a bit of unburned fuel which ignites as it passes
through the exhaust turbine. The effect is exactly the same as in
a jet engine: the expanding fuel/air mixture accelerates the
turbine, which keeps the turbo spooled up in anticipation of the
next throttle application. I believe this trick has also been
used to momentarily produce more boost on cars equipped with a
sanctioning-body-supplied blowoff mechanism (i.e., CART).
Jay
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