Headers vs 340 manifolds

The test makes no mention to carb/timing changes, only manifold changes. Need more information on the parameters for this shoot out.
you dont think west tech dialed it in? come on now
its a known fact many dyno test compared the 2 on a mild motor its not worth much 900 bucks fck no
if guys can run 11s and 12s with them that says enough imo
never mind the 10 second f a s t cars
900 bucks on tti never
thats twin stage 250 hp shot of juice