Power Pages - 2003 Honda S2000

The 4-2-1 constructed exhaust manifold was designed by 5Zigen engineers with equal length designed runners. Designed with smaller diameter piping, the header tapers out from 42.7mm and opens up to 50.8mm, finally terminating to a 60.5mm collector. This staggered header design enables the F20c engine to maximize its horsepower at high RPM while maintaining torque at low end

Removal of the factory S2K exhaust manifold isn't exactly an exhilarating trip to your local strip bar, but we found installation to be a bit easier when loosening the bolts to the front subframe. The subframe and engine will drop ever so slightly, creating an easier time at accessing the bolts to the header.

Exhaust Manifold

12-, 14mm combination wrench, 12 and 14mm socket, ratchet, extension, crescent wrench

60 minutes

With a quick spin on the dyno, we noticed a deeper growl emitting from the exhaust after installing the 5Zigen header. Along with a more muscular tone, the S2K responded well to the stainless header as the dyno graphs displayed a gain in both horsepower and torque from low rpm until redline. A gain of 3 to 4 hp and 3 to 4 lb ft of torque were found consistently throughout the charts as we compared the final header dyno numbers to our previous run.

Dyno 3: 5zigen 4-2-1 Stainless Exhaust Manifold
Peakhp 201.8 / Peaktq 129.2

HORSEPOWER GAIN
1500 to 3500 HP range: 2 to 3
3500 to 5500 HP range: 3 to 4
5500 to redline HP range: 4 to 3

TORQUE GAIN
1500 to 3500 TQ range: 2 to 3
3500 to 5500 TQ range: 3 to 4
5500 to redline TQ range: 3 to 5

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