I see mentioned Stainless Marine Gen 3 a lot.

I have Stainless Marine BBC exhaust manifolds from the early 90s. There is no Stainless Marine Logo or Lettering on the sides like the newer ones.

What are the Generation changes...and what gen would I have?
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Was there flow benefits with Gen 3s?
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I have the dry to tip style, with the 1/8" holes in the ends to cool to the tip.
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Just looking to see what my manifold limitations are for flow.

I've heard 800hp with little flow impedance for the Gen 3 BBCs.

Thanks,

Art