Restrictions in the exhaust system robs horsepower and torque especially on turbocharged cars. Thus, removing as much exhaust flow restrictions will increase horsepower and torque significantly. The factory catalytic converter found in the factory downpipe is a big culprit of this and is a major exhaust flow restriction. The factory catalytic converter is made up of catalyst material formed into "honeycomb" weaves. Exhaust gas must pass through these tiny "honeycomb" weaves on their way to the exhaust system thus causing a major exhaust flow restriction. It also causes turbulence after the catalytic converter which causes the exhaust flow to slow down (which increases restriction). By replacing the factory downpipe/catalytic converter with our Competition Series 4.5" Catless Downpipe, more power is unleashed!You will feel the difference instantly. While the 32whp and 16wtq gains are awesome, one of the best aspects of the downpipe is that the gains are not just peak gains. Examine the dyno graphs and you will notice the powerband shifting to the left. What this means is that turbo lag is reduced with power coming on faster. Gains are throughout the powerband as well. Your car will feel like a totally different beast.
The new turbochargers on the B58 engines utilize a much larger 4.5" outlet compared to the 4" outlet on the older N55 engines. If ER had decided to use a 4" downpipe flange inlet so that they could use 4" tubing, a "step" would be formed between the turbocharger outlet and downpipe inlet. Exhaust gas for the turbocharger would hit this "step" and a lot of turbulence would form at this point and cause backpressure. Backpressure this close to the turbocharger would greatly affect performance. Thus, to ensure that you get unobstructed flow from the turbocharger outlet to the downpipe inlet, ER had to CNC machine a new 4.5" flange to match. This allows a seamless transition and eliminate any possible turbulence which would cause backpressure.
Competition Series Catless Downpipes is constructed out of 100% 304 grade stainless steel and utilize mandrel bent piping. They are 100% TIG welded by in house fabricators and built in the USA. The factory turbocharger turbine housing utilizes a V-Band flange which has been duplicated and CNC machined cut out of billet 304 stainless steel. Stainless Steel CNC machined O2 sensor and laser cut brackets are TIG welded using stainless steel rods. The O2 sensor is positioned at the factory location. Since the outlet of the turbocharger is 4.5" and the factory exhaust system is 3", the factory downpipes reduces size using short transitions from 4.5" before the catalytic convert and 3" afterwards. Due to space needed for the catalytic converter, the factory downpipes reduce in size using very short transitions. Since catless downpipes delete the catalytic converter, more space is available. Thus, the ability to use very long transitions. These longer transitions allow the exhaust gas time to smoothly transition from the larger piping to the smaller. Also, by using a larger 4.5" pipe right after the turbocharger, turbo backpressure is significantly reduced. This results in less exhaust turbulence and backpressure which again improves throttle response and increase turbocharger spool times (less turbocharger lag).
Evolution Racewerks downpipes are designed to fit perfectly with either the factory exhaust system or your aftermarket exhaust system. There are no compatibility issues whatsoever. The downpipes will come by default in Brushed Finish. We also offer a Polished Finish as an option.
Ceramic Thermal Coating (adds $95) - The purpose of ceramic coating downpipes is to keep heat from the exhaust gases inside the downpipe from radiating out. This keeps underhood temperatures lower and less heat absorption by nearby parts/surfaces. Another added benefit is that by keeping in heat (energy) in the exhaust gases inside the downpipe, exhaust flow velocities stay high, resulting in lower backpressure. The ceramic coating also adds additional corrosion resistance. We utilize the best ceramic coating possible. Our thermal coating can resist up to 2000F of heat. It is available in black only (all the other colors cannot withstand the high levels of heat).
Additional O2 Sensor Bung (adds $20) - An additional O2 sensor bung can be added so that you can easily add a wideband O2 sensor and gauges for you to monitor air/fuel ratios. The additional O2 sensor bung will come pre-installed with a plug so that you do not need to run the O2 sensor right away.
Optional EGT (Exhaust Gas Temperature) Bung (adds $15) - An additional 1/8" NPT bung can be added so that you can easily add a EGT sensor and gauge. The optional EGT sensor bung will come pre-installed with a plug so that you do not need to run the EGT sensor right away.
NOTE: This product is intended for OFF ROAD COMPETITION USE ONLY. Not legal for use on pollution controlled vehicles upon public road/highways. THIS PRODUCT IS FOR SALE FOR ALL 49 STATES EXCLUDING CALIFORNIA. In addition to vehicle use verification, a Vehicle Compliance Waiver needs to be signed.
THIS ITEM IS NOT FOR SALE, INSTALLATION, OR USE ON LICENSED VEHICLES IN THE STATE OF CALIFORNIA.