TiC exhaust system versus stock EVO system: Gains are mostly at the top end.
Our first mod is one of the biggest bangs for the buck we've witnessed. We simply flipped our stock airbox lid and dropped in a K&N replacement air filter element. The K&N uses a washable and reusable cotton gauze element that flows much better than the OEM oiled paper part ever could. K&N assured us our replacement filter was going to surprise us but we remained skeptical. We were amazed to pick up 4 whp at the peak, resulting in 269 whp at 6,740 rpm. The filter also allowed for increased power throughout the powerband, as much as 8 whp in certain spots.
Next up is our cat-back exhaust. Now just about every EVO in these parts sports some sort of cat-back exhaust, in fact we can't remember the last time we've seen an EVO without one. Since Project EVO's modifications will inevitably get rather extensive, a large diameter exhaust was chosen. And since we also plan on tracking our all-go no-show EVO, weight became a consideration; after all, the EVO is somewhat porky to begin with, with an exhaust that isn't exactly light. Enter GReddy's TiC system.
The TiC features big 80mm tubing, one of the only non-special order exhausts available in the U.S. to offer such sizing. The EVO TiC is designed with minimal bends for less backpressure and better exhaust velocity. It's also light, featuring thin-wall stainless steel construction, hollow stainless hangers, thin but strong stainless flanges and a titanium tip. The TiC exhibits extremely low backpressure with its straight-through perforated core mufflers filled with GReddy's unique composite cube packing. The TiC is more than 20 pounds lighter than the stock exhaust. What we found amazing was that despite the system's race-inspired, straight-through construction and baffle-free mufflers, it was nearly as quiet as the stock muffler-that's with the optional silencer removed. On the dyno we found that the TiC gave us 8 hp on the top end boosting our output to 276 whp at 7,050 rpm. The exhaust was limited to power increases up top, which leads us to believe that major restrictions lie forward of the cat.
Next up is XS Engineering's intercooler hard pipe kit. The kit replaces the restrictive stock piping with smooth, mandrel-bent polished aluminum tubing. It works with both the stock and XS' upgraded front-mount intercooler. A smaller battery, however, is required when using the XS kit-or you can do what we did and relocate the battery to the trunk. A smaller or relocated battery allows XS' hard pipe kit to take advantage of smoother bends for less turbulence inside. It's apparent XS took their time here, carefully shaping and routing pipes to keep bends at a minimum and airflow high without simply resorting to larger tubing, which often leads to poor throttle response and increased turbo lag.
The hard pipe installs relatively easily but we did have to remove Project EVO's front fascia-also an easy job. It's almost as if the EVO was designed to have its bumper easily removed. XS assured us that the power gains would please us but, again, we were skeptical. We just didn't think the stock intercooler plumbing was all that restrictive looking. A trip to the dyno yielded surprising results. The XS piping resulted in a 7whp gain for a new high of 284 whp at 6,800 rpm. Power gains were generally across the board with improved low-end response. Peak gains of more than 12 whp were realized past peak power. What a pleasant surprise this was.
XS Engineering's intercooler hard pipe kit features smoother, swept bends and less kinked
Dyno testing the intercooler piping surprisingly showed large gains across the board.
Intercooler inlet pipe as installed.