2008 Mitsubishi Evolution GSR - Proving Grounds

The New Era Of Affordable Titanium Exhaust Systems Is Here.
Description
We've all seen (and probably drooled over) titanium exhaust systems found on some of the best time attack machines in Japan. The angled cuts and precise welds are a sight to behold. Unfortunately, the cost of one of these systems is in excess of $2,000 to $3,000 - out of the average consumer's price range.

Tomei has seen the need for an affordable, lightweight, purpose-built performance exhaust system in the market, and after long periods of testing and development, its ExpremeTi exhaust is finally here. The system weighs in at a scant 9.7 lbs, 35 lbs lighter than the stock exhaust. A reduction of that much weight is simply impossible with a conventional aftermarket steel system.

However, weight savings is only one part of the many advantages to Tomei's ExpremeTi system. Titanium is a very strong and durable metal. It's also highly resistant to heat and corrosion, meaning the piping and muffler won't fatigue or wear out even under intense track conditions. Tomei has also gone to great lengths to ensure that the Titanium used in its exhaust system is high grade yet affordable for the average consumer.

Since the muffler is full titanium, a strong stainless steel band is used instead of welding a bracket to the muffler. This reduces stress on the exhaust from vibrations and movement, ensuring a crack-free exhaust for years to come.

Since the muffler is full titanium, a strong stainless steel band is used instead of weldi

The 3-inch muffler has been built with maximum flow in mind, and with the use of long-thread fiberglass it provides excellent sound reduction and copes with high temperatures much better than the conventional short-thread fiberglass packing. Titanium is incredibly difficult to weld, yet one glimpse at the welds on the piping and you'll see that they're all impeccable -an excellent sign of quality. Instead of flanges, a slip-fit design is used to ensure a leak-free environment and secure fitment. The optional test pipe is also made of full titanium and further reduces weight by 12 lbs over the factory catalytic converter. With both the ExpremeTi exhaust and test pipe, a massive reduction of 47 lbs over stock is achieved.

The MSRP of the ExpremeTi exhaust system is $1,290, a bargain considering the cost and involvement to make such an exhaust system. When you consider the solid performance gains and weight reduction, this is the only system on the market of its kind. Currently, it's only available for the EVO X, but more applications are coming: Subaru WRX and STI, Genesis Coupe, Nissan 350Z and 370Z, S13, S14, S15, RX7, Skyline and more.

Results Our EVO X project car was the perfect candidate for this exhaust because it already had an upgraded intake, intercooler and reflash. With the stock exhaust and catalytic converter, the EVO turned the rollers to 298 whp and 331 wtq on Garage GT's dyno dynamics dynometer with a correction factor of 1.15. This is a low-reading dyno, so for reference, a stock EVO X makes 225 whp. We then bolted up the Tomei ExpremeTi test pipe and exhaust system, and the results were nothing short of impressive. With no tuning or turning up the boost, the system picked up an instant 27 whp and 3 ft-lbs of torque. The dyno chart shows power and torque come up dramatically in the mid- to upper-rpm range. The exhaust also allowed the turbo to spool several hundred rpm quicker, as you can also see on the next page [1].

We then decided to test the system with Cobb Tuning's high-flow catalytic converter because not everybody wants to run around on the street with a test pipe. The ExpremeTi exhaust managed to make 316 whp and 326 ft-lbs of torque [2] - also great numbers for just bolting on an exhaust system. For the final test, we installed the silencer to see how much power it would rob. After 5300 rpm, power dropped off to 317 whp compared to the 325 whp without it installed [3]. That's not too bad at all, and considering how quiet the system gets with the silencer, it's worthwhile to have it in for the street and uncorking it for the track.