Twelve exhaust systems, 36 dyno runs, ten hours of wrenching, a couple pizzas and some burned flesh; it's all in a days work. Sometimes we here at Turbo get a little ambitious. We can only blame ourselves; but we do it out of good intentions. Our famous exhaust shootouts receive a lot of love from you, the readers, but they certainly leave us battered, bruised and in this case, burned (enter evidence exhibit A, my left arm). Running on pure adrenaline we installed and tested twelve exhaust systems from sun up to sun down on our dyno drone at XS Engineering in Huntington Beach, California.

Due to the popularity of the EVO VIII and the many requests we have received, we decided to figure out which exhaust system is the best for this Mitsu. In order to do things fairly we solicited exhaust systems from every aftermarket manufacturer we could find, twelve of which sent an EVO VIII exhaust over for us to test. We invited all of the manufacturers out to witness the installation and testing. We dyno'd all of the systems on the same car, on the same day and at the same facility. We gave each system three power runs and tested the decibel level at idle and 3000 rpm. We replicated the same dyno run procedure for each system (same fan, no ice, heater on between runs, off during the run, etc.). It was the perfect day for dyno testing, as ambient temperature was within two degrees from sun up to sun down. We know since we data logged the ambient temperature on all the runs.

Rolling up on the four-wheel dyno is our Project EVO VIII. Having played with a few EVOs since its introduction here in the States we have noticed how incredibly sensitive the factory ECU can be. Install an exhaust, downpipe and cold-air intake and instead of gaining horsepower you can actually lose it. Knowing that most EVO enthusiasts will likely modify their vehicle with more than just an exhaust system we opted to test the 12 exhaust systems on a mildly tuned Evolution. Our Project EVO was the perfect candidate. Since our EVO already had an AEM EMS installed we were not worried about the factory ECU taking over the control of fuel and ignition timing. Project EVO is also equipped with nearly every possible bolt-on; AEM cold-air intake, DC Sports downpipe, DC Sports turbo manifold, XS Engineering front-mount intercooler and hardpipe upgrade, Buddy club 264 degree cams and AEM adjustable cam gears. To keep tabs on boost pressure a Blitz i-Color boost controller was preset to a duty cycle on all the runs so there would not be any boost differences unless one system was more restrictive than another.

So after ten hours of testing who is the top dog? Well it depends on what you are looking for. Several of the systems tested made almost identical power so it all depends on the style, type, construction, etc. All we know is that if you are in the market for an Evolution exhaust we've got you covered.

SOURCE
5Zigen Injen
A'PEXi USA RSR
Blitz
4879 E. La Palma Ave. Ste. 206
Anaheim
CA  92807
Skunk2
http://www.skunk2.com
Espelir (Mackin Industries) Tanabe
GReddy Turbo XS
8041 Queenair Dr., Unit 2
Gaithersburg
MD  20879
3-01/-977-4727
www.turboxs.com
HKS USA
13401 S. Main St.
Los Angeles
CA  90061
3-10/-763-9600
www.hksusa.com