Forced induction/supercharger

[atsakiri at ford.com]

> Actually I am considering a small Roots (Whipple Charger) Blower.
> When I used the term forced I meant it :)
>
[snip]
> 
> I get about 120 Hp now and Set an arbitrary target of 140 as a design 
> goal. The trick is I want to do a bypassed turbo or Super charger
> with a demand clutch to shift it in and out of the system. I'm leaning
> toward the mechanical blower because in my 4x4 throttle response is an 
> issue.
[snip]

You can also "bypass" a mechanical supercharger.  The 1.5 liter
Roots blower on the supercharged 3.8 liter Ford V-6 recirculated
the air from the supercharger outlet (after the intercooler 
actually) back to the supercharger's inlet.  Air is still pumped
around the loop, but against a very low pressure differential.
When boost was desired, the recirculation path was closed.  Air
then flowed only to the intake manifold.

The recirculation valve was a small throttle blade-like valve,
moved by a vacuum actuator.  It could also be operated based on
throttle or pedal position.  This approach might be less 
complicated and less expensive than a supercharger clutch.


                    recirculation valve
                   /
        +---------|X|--------------<---+
        |                              |
        |     -------       -------    |      ----------
        |    |       |     |       |   |     |          |
   -->--+----|  S/C  |-->--|  I/C  |---+-->--| manifold |-->
             |       |     |       |         |          |
              -------       -------           ----------




Anthony Tsakiris


S/C = supercharger
I/C = intercooler

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The opinions expressed are my own and not necessarily those of my employer.