I want to buy a HKS Exhaust manifould and downpipe (for a MY00), a powergain of 25 bhp is promised(manifould only). Can this be true, to my knowledge the motor wil have more low-end power with a manifould.
Has anyone experience with these manifoulds,
please let me know.

 

Yes it`s true. But you loose typical boxer sound and you can spend your money for Unichip or Link + FIC whitch gain more HP. But if you have read last Banzai magazine there is an art. about atmosferic V-Tec Civic /Shake battle and roll/. This Civic have heat insolated manifold for faster gas flow with something like Nomex textille. Faster flow = more energy for turbo = very interestig!!!

 

I thought the HKS item was a 'tuned' manifold, rather than an equal length manifold.

If it was equal length, then yes you would lose the sound of the boxer engine. Although I though the HKS items were 'tuned', so although one set of pipes is longer, it's still unequal and retains that 'boxer beat'.

That's why the HKS item is of more interest to me, than say an equal length manifold.