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Old 11-20-2015, 01:14 PM   #18 (permalink)
BabyDiesel
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Quote:
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

Quote:
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?

Pi(R^2)
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!
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