Quote:
Originally Posted by dlouie87
looks good. what are the dyno # on this piece?
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http://grassrootsmotorsports.com/art...ive-decisions/
The HKS system uses yet another design for piping, as it features an H-pipe. This allows for the equalization of exhaust gas pressures, but it doesn’t encourage lots of commingling of the*streams.
The HKS also has a second set of resonators that help smooth out the exhaust note—and smooth it is. The HKS was the quietest of the bunch at idle, yet had a nice tone when accelerating hard. We found it difficult to tell that we had a performance exhaust on the highway, but around town it sounded just a bit throatier, much like a factory performance*exhaust.
Another neat feature of the HKS is a bolt-on reinforcement plate that limits tip misalignment as the exhaust system warms up. You might never notice that little brace, but you would certainly notice misaligned tips. Unfortunately, those tips didn’t quite seem appropriate for a car of this type. The large-diameter, blue-tinged titanium tips might look more fitting on a Japanese sports car rather than a European sports sedan. Future HKS systems sold through BimmerWorld will feature more traditional-looking*tips.
Despite the near-stock sound levels, the HKS exhaust system was the chart-topper for both horsepower and torque. We saw an additional 13 horsepower and 8 lb.-ft. of torque, with good gains at every rpm point above 2000*rpm.