408 Stroker

mopardude318 said

Well that's fricken RAD!! Jeez, after I buy a set of 1-5/8 to 1-3/4 they come out with these!! How much of a difference do you think they would be on my 408 stroker? My engine dyno'd at 533 HP/513 FT LBS with the step headers..I wonder how much more I could get out of it with the 1-7/8" headers......

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You might be surprised! I've seen the smaller headers on more than one build work better than the large tube headers.
Remember if the ex. port is only so big, and flows so much, a bigger tube will almost always slow the ex. speed down resulting in less velocity in the ex. tract. This can hurt the heads ability to "blow down".
I've seen this in Big blocks alot. We did a basic bracket type BB engine, 4.400x4.150 with Eddy MW victor heads and Super victor intake, small roller cam, 1050 dom, 12.9:1 and HOOKER 2" headers and it made 776HP at 6400rpm!
A larger tube may have helped, and may not have helped. But that's a pretty good HP # from a mild build and mildly ported heads that had more in them.
So 1 7/8 for a sb with small ex. ports is likely overkill unless it's a high rpm (7500+)engine.
Just some food for thought...