997 Carrera GT3 Conversion Exhaust

Special design system for 997 Carrera with GT3 body kit.

The first point that stood out, was the catalyst design. 600 cell oem cats, and absolutely no balance present in the factory exhaust. replacing this unit for a 200 or 100 cell sports catalyst we were able to achieve some moderate power and torque gains. the second design alteration was to remodel the way in which the exhaust gases interact from opposing banks. Replacing the two piece design for a single piece with our trademark tight radius, laminar flow X pipe, we were able to alter the exhaust pitch, and smooth out the imbalance, this resulted in a far more high revving race car like sound. This was a design innovated and pioneered by kline,

The factory silencers, heavy, cumbersome, and restrictively chambered, produce a tinny note to the exhaust. We needed to enrich the sound, as well as improve gas transit, and simultaneously reduce weight. weight reduction and sound enrichment proved to be fairly straightforward with the simplification of the silencer design and removal of the multiple chambers. the addition of a single chamber volumetrically tuned towards low rev resonance, removed bass noise at cruising speeds, while a rich raucious vocal is achieved at hard throttle above 4000rpm.


Cross Section

Cross sections in pre catalyst; 57mm OD chosen specifically to keep lambda ranges in A/F stoichiometry.

Post catalyst cross section; 63mm OD into 1D CLR tight radius X pipe.

Silencer sections; 63mm OD pre silencer, 57mm OD post silencer, single chamber with acoustic fill section.


Available in standard 304 grade stainless steel weight
silencers 6kg each
cat section 6.1kg
total 18.1kg

Inconel 625, formula one grade exhaust material weight
silencers 3.8kg each
cats 3.5kg
total 11.1kg

manifolds 2kg each

Titanium G2 silencer sections are also available, weight is compariable with inconel


100 cell 200 cell HJS cats are used as standard.