Re: turbo theories Part 7.32.dRe: turbo theories Part 7.32.d

[RayVR4@aol.com]

>Think of the bypass valve and a "recirculating"
>valve. It "bypasses" the engine, not the turbo, and feeds the compressor
>output back into the compressor input "bypassing" the engine. Also, to
>keep the turbo spinning you want to keep the WG closed as much as
>possible, so all the exhaust gas passes through the turbine to keep it
>spinning.

Actually I was looking at the exhaust side of the turbo and was wondering if
recirculating exhaust gas by opening the wastegate would help.  Thinking
about it some more it doesn't look like it would work.  There have been a few
manufacturers that have made turbos with variable angle vanes on the turbine
side which can give the high flow of a large turbo and the spool up of a
smaller one.  There's even one that eleminates the need for a wastegate but
their cost and unproven reliability have kept them from becoming popular.

>You are indeed correct about the bottom end power (something the 90 knows 
>nothing about...) and it's simplicity....
>Whenever we 'talk' about this topic, his point of reference is a Dodge 
>laser turbo or possibly an SVO.. any mass production small spooling 
>turbo. Mine is more of an Esprit or S4 etc... any turbo that is done 
>'right', not like somtheing that came out of detroit (Ill get hate mail 
>for this one for sure!), where the the stock laser is 140 horse, and the 
>turbo laser is 145 horse (hypothetical #'s but you get the point!).

Not hate mail but to clarify, the turbo versions of the Mitsu Eclipse, Eagle
Talon, Plymouth Laser and Mitsu Galant VR-4 (which I drive) all use a Mitsu
2.0L engine making 195hp w/stock boost.  Boost starts at around 2200rpm and
maxes by 3000rpm.  With just bolt-on intake, exhaust, and wastegate
modifications you can get 240hp reliably from the engine and there's
currently quite a few people running reliably over 300hp without ever having
opening the engine and a couple running over 400hp.  It's also the same block
used in the Mitsu rally cars.  Though it's not quite as sophisticated
(mechanical boost control & integral wastegate) I'd rank it right up there
with the Lotus and Cosworth 4 cylinder engines.

Ray