The gains are noticable in all rpm range no matter the manifold formation but depending on the header formation(4-2-1, 4-1, 4-2-2-1........LOL this reminds me football lineups!! ) the gains are concentrated on eihter high or low rpm. When going for mods like ECU, cams, head-work etc.....you should replace stock B-Series exhaust manifold since its one of the most restrictive OEM parts that destroy the whole project if not replaced!hi, thanks for the info! so do you recommend this header?
not too sure on the 2.5" header on my B16A. . . i know the benefits of headers are noticeable on the high rpm, but how does it feel @ the low rpm? as its my daily ride.
i have just adapt the header to the decat !( i have picture if you want)
to finish my short experience this header is a good compromise the cost half than a toda for performance close to it!!