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Re: Changing the Bomb

Richard Funnell wrote:
> I don't know about the harmony concept.  I suspect it's just a case of
> wanting to use a common power source (the high-pressure pump) for more than
> one function.
> >
> >Best Wishes,
> >
> >Alex Kowalski
> >'84 4KQ
> Richard Funnell,
> San Jose, California
> '83 urQ
> '87 560 SL

Drats, foiled again by ignorance!  I'm not a turbo expert because I've 
never owned one, but I should have remembered this fact about turbos and 
vacuum and such. BTW, what do you think on the subject of turbos, 
maximum boost, and altitude, regarding the response to the <Plethora of 
Questions...> post by Robert Houk?  

I still believe that whether you dynomometer a Turbo engine at Daytona 
Beach or the top of Pike's Peak, you'll eventually get the same final HP 
rating because the wastegate spring doesn't care about relative 
atmospheric pressure and instead opens only once it is pushed with 
sufficient force.  This is "maximum boost", as predetermined by the 
factory, and therefore entails a certain number of air molecules being 
forced through the intake, followed by fuel and such.  Unless, that is, 
you are so far out of the atmosphere (...your Audi is carried aloft 
beneath an SR-71 Blackbird and released because you have been Chosen to 
compete in the Autocross of the Audi Gods at 75,000 feet...Gasp!) that no 
matter how fast you spin the turbocharger there is virtually no air 
left to compress. The only difference altitude should make are turbo lag 
and low RPM/boost "driveability" because turbo motors often have a lower 

Maybe secondarily they correlate the steering and brakes.  It has felt 
like that to me on every total-hydraulic system I've driven versus the 
other kind.  Could also be my own aesthetic judgment overreaching 

Best Wishes,

Alex Kowalski
'84 4KQ