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      07-11-2013, 05:58 AM   #255
Mangler
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Quote:
Originally Posted by Boss330
Quote:
Originally Posted by Mangler View Post
What ever happened to variable vane technology that is used on Diesel engines? Are they too big and heavy to spin up fast enough?

Just decouple a supercharger that comes online when the primary turbos run out of steam. This would carry the power to redline that everyone is so worried about.

T
Variable vane is better for response than std, but it doesn't have the ability to regenerate energy from the exhaust. Nor is it able to operate independent of exhaust gas flow. An electrical motor/generator unit (MGU) can do both.

An MGU can spool up the turbo from 40,000 to 120,000 rpm in less than 450 ms. That is as near as instant!!!

And it's not just power to the redline that is an issue, it's response in the lower rpm scale (or turbo lag). With an MGU you can combine a fairly large turbo for high rpm's with the response (or in fact better response) of a small turbo
Why not use the MGU on smaller variable vane twins rather than the large single but make them large enough to flow all the way to the top end. I'm still hoping its twins and not a large single.

T
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