PowerPages: 2004 Scion tC

Dyno 4: DC Sports Ceramic Race Headers

Pros
When compared to the stock headers, these babies rock. This is because they are composed of equal-length runners that lead to a four-into-one collector, whereas the stock headers are shorter and collect at the catalytic converter. In addition to design, fitment is right on, making for an easy and quick installation. These headers made good power, about 8.5 hp and 7.8 lb-ft of torque. Too bad they're not legal for street use.

Cons
Since these race headers bypass the stock catalytic converter, they are for off-road use only. Don't expect to pass visual or emissions with them.

Notes
The stock O2 sensor that mounts in the collector on the stock header has very frail threads, and if not removed meticulously, can strip easily. As always, be sure to allow adequate cooling time so you don't burn your hands on the header. Spray everything down with WD-40 to make the disassembly process easier.

Tools
Ratchet, 10- and 12mm sockets, 6-inch extension, 10mm wrench

Parts
Ceramic coated headers and stickers

Installation time
20 minutes

Temperature
Air temp @ 71.7 degrees Fahrenheit
Temperature difference from previous run: +1 degree Fahrenheit

2000 to 3500 HP range: 0 to 8
3500 to 5500 HP range: 3 to 7
5500 to redline HP range: 5 to 8

2000 to 3500 TQ range: 1 to 15
3500 to 5500 TQ range: 6 to 8
5500 to redline TQ range: 6 to 8

Peak HP: 156.0
Peak TQ: 163.8

By Richard Fong

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