bypass valve installation, 5kcstq

[frank j. bauer]

At 06:02 PM 1/19/01 -0700, you wrote:
>I eventually saw a picture of a modified michelin man hose, for a 
>bypass valve.  I was wondering what other installation methods are 
>used to install one.  Are there any other pictures of installations 
>online?

you can theoretically install the byass anywhere between the turbo and
throttle plate and the return anywhere between the air sensor and the turbo.

>They don't have to be installed in the michelin man hose, do they?  
>Can't they be before the intercooler?

the advantage of the mm hose installation is that it puts the relief valve
at the point where the pressure spike starts when the throttle valve slams
shut, meaning faster response and saving the ic from experiencing most of
the pressure.

>Also, is there a benefit of having the bypassed air go through the 
>intercooler twice?  Is that what it's doing in this example?

it doesn't necessarily go through (just) twice, it just keeps recycling
through the turbo/ic.
the actual purpose is that all metered air stays in the system.
it can't hurt that the pressurised (heated) air is cooled again.
the real side benefit is that the air recycling through the turbo keeps it
spinning for a while so that turbo response is improved when the throttle
reopens.
without the bypass, the pressure spike would stall the turbo.

frank