Contour Enthusiasts Group Archives Forums Modifications Duratec Performance Intake manifold design

Originally posted by todras:

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{TH}NOT!!!!....they are designed to keep intake gas VELOCITY high to keep cylinder filling at max re:better IMEP and cylinder scavange!!!!!!!!!..And the initial design was by Porsche not Watson.

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the initial design yes...
but watson made this. If porche designed it then why did watson make one?

Originally posted by svtProdigy:

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Originally posted by todras:

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{TH}NOT!!!!....they are designed to keep intake gas VELOCITY high to keep cylinder filling at max re:better IMEP and cylinder scavange!!!!!!!!!..And the initial design was by Porsche not Watson.

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the initial design yes...
but watson made this. If porche designed it then why did watson make one?

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Originally posted by tour96SeVT:

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Originally posted by svtProdigy:

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Originally posted by todras:

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{TH}NOT!!!!....they are designed to keep intake gas VELOCITY high to keep cylinder filling at max re:better IMEP and cylinder scavange!!!!!!!!!..And the initial design was by Porsche not Watson.

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the initial design yes...
but watson made this. If porche designed it then why did watson make one?

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...post a pic of this on the engine if you could...i remember seeing pics at one time or another

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this was my 3.0 block and 2.5 heads.

Originally posted by Auto-X Fil:

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First off, flow is turbulent pretty much everywhere in the intake. There's no laminar flow in a system like this. It's pressure and velocity changes that designers try to minimize. Ideally the air wouldn't have to make a bend like it does, but it's far more important to get the length right. Packaging then dictates that it have bends. Variable intakes are now a pretty common thing on more potent engines, but it was fairly new, and quite an impressive feature on the original engine. Exhaust and intake both work best when they are long and small diameter at low revs, and short and wider at high revs. This intake, as you can see from the tubular pictures, delivers air through narrower, long tubes until the secondaries open, then through both them and the slightly wider, much shorter secondary feeds. Without the secondary design, the engine would just die at low revs. Imagine if the torque curve at 4k continued all the way down, without that hump... it would be pretty lousy at low revs, like most engines of this displacement.

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I see your points Consider a manifold with a very large central "log" (like the cobra intake). Run the primary runners underneath this log and have them enter the log on the opposite side. The secondaries can be a straight shot from the bottom of the log directly into the LIM. I know design considerations dictate this type of manifold wouldn't work in an OEM situation as it'd be too tall for a production vehicle. Aftermarket? maybe This type of manifold would eliminate most of the sharp bends that are inherent in the stock svt setup.

Originally posted by Auto-X Fil:

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First off, flow is turbulent pretty much everywhere in the intake. There's no laminar flow in a system like this. It's pressure and velocity changes that designers try to minimize. Ideally the air wouldn't have to make a bend like it does, but it's far more important to get the length right. Packaging then dictates that it have bends. Variable intakes are now a pretty common thing on more potent engines, but it was fairly new, and quite an impressive feature on the original engine. Exhaust and intake both work best when they are long and small diameter at low revs, and short and wider at high revs. This intake, as you can see from the tubular pictures, delivers air through narrower, long tubes until the secondaries open, then through both them and the slightly wider, much shorter secondary feeds. Without the secondary design, the engine would just die at low revs. Imagine if the torque curve at 4k continued all the way down, without that hump... it would be pretty lousy at low revs, like most engines of this displacement.

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