Nissan 370Z Automatic Transmission performance parts Dyno Thrash!

Stillen's 370Z exhaust features dual mufflers and all stainless steel construction

The dual muffler cans on Stillness 370Z exhaust are made of 304 stainless as are the tips

The Stolen 370Z exhaust is smaller in diameter than the Berk cats at this point at 2.25 inches.  We think it would make more power at 2.5 inches

The Stillen 370Z exhaust goes from 2.5 inches in diameter to 2.25 inches and back again in several places along the flow path.  If it were 2.5 inches all the way through, it would make more power

Next up was Berk Technology high flow cats and dowpipes. The Berk parts have proven themselves to be good performers in our previous test but would they work as well on the stingy Superflow dyno. The Berk Technology cats have a free flowing 200 cell count spiral wound metallic substrate.　 The substrate is the honeycomb-like stuff inside the cat that the exhaust gasses pass though that cleans the exhaust stream.　 A metallic substrate has thinner walls with less cross sectional area than the ceramic material used for the honeycomb in most factory cats. Thinner walls mean larger internal passages in the honeycomb and thus less backpressure.　 Each passage is called a cell and a 200 cell count means that this honeycomb has large diameter cells for low restriction.　 Stock cats usually have cell counts in the 400 range and thicker walls on the cells making for much more flow restriction.

The Stock 370Z cats neck down at the inlet considerably compared to the Berk parts

Berk Technology 370Z high flow cats feature high quality 304 stainless steel construction, extra 02 sensor bungs for wide band sensors, factory like hanger brackets and smooth turbulence free bends

The stock cats have a small 46mm inlet with a 60mm outlet, with tiny under 2" tubing.　 The Berk parts are a much bigger 2 1/2" or 68mm in diameter all the way through with smooth mandrel bends to really uncork the system in this area. The Berk parts are high quality pieces featuring 100% 304 stainless steel　construction. The cases, tubes and flanges are all high grade 304.　 The transition from the tube to the cat is gusseted for additional strength.　 For tuning convenience, bungs for a wide band A/F O2 sensor are located in both downpipes before the cats.　 For an easy installation and a leak free seal a factory exhaust manifold compatible gasket is provided.　

The Berk 370Z high flow cats have a bracket that bolts to the factory support.  This is important for long term durability and insuring that the exhaust won't rattle.  Exhaust rattle can trigger false knock causing the ECU to wrongly retard the timing

The Berk high flow cats did not disappoint posting the highest gains of any part installed in our test putting out 6 more whp and an impressive gain of 6 lb/ft of torque for a peak power reading of 282 whp and 225 lb/ft of torque. What impressed up the most is that the Berk 370Z high flow cats delivered their peak gains nearly across the board. Although the numbers themselves don’t tell the whole story, the gains in area under the curve, the part that actually makes you faster sure do. The Berk high flow cats are our power shootout winners and are the best bang for the buck part we have tested for the 370Z so far.

Berk Technologies Nissan 370Z high flow cats gave the best power results of all the parts we tested with great gains across the entire powerband for maximum gains under the power curve, awesome!