Match Race = 1968 Road Runner '383' vs. 1964 Belvedere '426-S' Street Wedge

OK ya got me all fired up.. I'll take the 426 Street Wedge, BUT the part that got me was these damned exhaust manifolds.. why so much different then the normal ones used on the 440 or hell I even think I seen the same ones on the 413.....But this one has "log" looking headers? What gives? Weren't the heads from the factory for the 413, 426 and the 440 all the same? IN the day that is! NOT aftermarke stuff....

OR are these manifolds seen here, common and I haven't noticed them, till now?

HP manifolds aren't actually all that good, IQ52 did some dyno testing with various parts on a '72 440:

http://www.forabodiesonly.com/mopar/showthread.php?t=249866