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Old 11-20-2015, 01:14 PM   #18 (permalink)
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Originally Posted by Daox View Post
Thanks for all the tips guys, there is some good info there.

I do realize the Metro's exhaust ports are rectangular. I'll be getting to that. The initial image you saw was just me throwing together a rough draft so to say. There will be transitional pieces going from rectangular shapes to round.

This will be a long tube header design, this helps low rpm power/efficiency. I'm not exactly sure on the length yet. I'm still working that out.
We are all looking forward to what you come up with

Originally Posted by ksa8907 View Post
Ok got it, thanks for clarifying. So we would also want primaries that have roughly 25% less cross section? Around 1.375 - 1.4" inside diameter?

Since we are discussing volume, yes!

The math worked like this for me - A 1.5" primary SBC Header will have a primary cross section of 1.767". 25% of this would be 1.325". Since there is a greater focus on low-end, I believe Tim could go slightly smaller. A 1.25" primary gives ((0.625" x 0.625")3.14), which equates to a 1.227" cross section, a 30.6% decrease.

So 1.25" seems to be the front runner unless there is some specific exhaust information that we are missing...

Edit: Tim posted right before me. Throw all this malarky out the window!

Remember, thank a fellow EM'er for a helpful post!!!
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ZX2 Aerodynamics: Shooting for 0.15 Cd
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