182 manifold is a waste of time to be honest
just use the 172 manifold and a 2.5inch manifold back system
Fred i went from 172 manifold and dekat to 182 and dekat and I feel the car faster from 2500 to 5000, acceleration time are better too, 50-90 kph (2nd gear) from 3"5 to 3"2, and 90-130 (3rd gear) from 5"1 to 4"7...I wouldn't say they're useless.
I have the 2.25 inches superstealth k-tec exhaust.