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Dynamohum Dynamohum is offline
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Join Date: Jan 2008
Location: Midland Ontario Canada
Posts: 173
Originally Posted by WERK-I View Post
Not to rain on anyone's parade here.

But to have have an effective twin scroll turbocharger, shouldn't you be working with equal length tubed primaries? I'm not saying you aren't going to see some gains with the OBX headers, but it probably won't be what you expect on low to mid-range rpm's.

Ben, your work, as usual, is beyond reproach. Excellent craftsmanship.
Your not raining or anyone's parade Its a great question and something that have much time thinking about.

Ideally I would prefer to have equal length primaries with an i.d. matched to the flow requirements but with the the least amount of tubing volume. From what I have learned; There seems to be a trade off between equal length primaries and the increased volume (adding to turbo lag) that they add in which also increases the surface area potentially reducing the heat charge to the drive the turbo.

To me the ideal equal length is much harder to build in a single turbo design and you end up with compromising results. There is a trade off between length and volume with a turbo header design. It is a shorter run and to me easier to build a equal length side mount header for dual turbos.

So the Question becomes, Does the gains from equal length primaries out weight the gains from a lesser volume system?

Perhaps the ideal system would be one that can most effectively use pulse timing of equal length primaries with a volume that contributes the least amount of lag.

Personal opinion: I think that thermal barrier coatings would benefit either design when done properly and that's why I'm willing to experiment with TBC.
Thank You for your time, Paul. We do because we can.
87 911 3.2 (Turbo conversion, build in progress, Thermal Barrier Coatings, High Pressure Dry film coatings) Modified heads, boat-tailed case, ARP hardware, OBX Header, 930 clutch disk, G50 Trans
89 5.0 Mustang convertible (For Sale)
Old 02-22-2009, 04:34 AM
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