AW: Intake manifold construction, intercoolers

[The Dupuis]

> > Heck, then make it a 7 butterfly system.  Or even 8.
>
> To what end? Idle control? Throttle re-opening response by closing
> off the plenum as well as the runners?

Um... I think he's making fun.


> OTOH, if you instead throttle the runners, the 'plenum' is already
> filled with high-pressure charge and starts to fill the runners
> sooner from the reservoir in the 'plenum'. As the throttles close,
> the reservoir accumulates some pressure and a subsequent re-opening
> of the throttles can benefit from the store if the over-pressure
> hasn't bled out through the turbo.
>
> Which system will have less lag?

Relatively high-pressure - i.e., not at 15" vacuum but at atmospheric or
just under on an N/A car or possibly much over on a turbo.  Much quicker
throttle response, possibly more turbulence at part throttle but the plates
should keep everything in line at WOT, and the turbulence might be good for
air/fuel mixing.
>
> > > > I thought individual throttle-bodies are normally used for engines
> > > > with long duration cams to avoid cross-flow and get better
> > > > idle/part throttle response ? I want to avoid the extra work (and
> > > > money) integrating 6 TB´s and linkage.
> > > Individual throttles are used where throttle response is required or
> > > where there's no common plenum.
> >
> > Or when looking for complex answers to simple guestions.
>
> That may be the case. It could also be ricers using them for
> brag-value.
>
> A great number of successful competition vehicles do use separate
> throttles; typically slide-throttles because they can afford them.
> In terms of flow at part-throttle, the slide-throttle offers little
> advantage at much greater risk of sticking (or leaking in typical
> setups).

The Euro-spec BMW M3 uses 6 throttles, doesn't it?  Seems to work okay there
;-)
>
> You mean
>   "Everything should be as simple as possible; but no simpler?"

LOL!!!
>

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