Engine Drivetrain 2nd Gen S Cold Side Boost Tubes

Discussion in 'Tuning and Performance' started by Dwight, Apr 30, 2011.

  1. Dwight

    Dwight Racing with the Gods
    Lifetime Supporter

    Jul 7, 2009
    San Marcos, Calif.
    +12 / 0 / -0
    I've steered clear of the all silicone cold side boost tubes since being told they were just engine bay bling and produced no noticeable increase in performance, just deleted the noise maker. Was looking at NM's hard tube and noticed it was 9mm bigger then the OEM (59mm vs 50mm) and was a continuous ID from IC to throttle body with no neck-down in the middle. I thought 9mm was no big deal until I did the math. That 9mm represents a 38% increase in potential air flow rate! I think NM's claim of a .5psi increase in boost could be a little conservative. I'm pushing about twice OEM boost so I ordered mine from North American Motorsports an hour ago! Will keep you posted. :idea:
  2. countryboyshane

    countryboyshane New Member

    Jul 23, 2009
    Diesel Engineering
    Bloomfield Hills, MI
    +77 / 0 / -0
    I would describe it as a shift in the torque curve with minimal gains. The narrower OEM tube gives better charge air flow at lower engine speeds, but is a little restrictive at higher engine speeds. With the NM tube the lower engine speed response is delayed a little, but now there are better flow characteristics at higher engine speeds, especially 4500rpm+. It is a trade off depending how you want the car to behave. Bigger does not always mean better.

    The best charge air tube to modify is the "hot side" tube. Guaranteed gains in power/torque by getting rid of that stupid silencer.
  3. Way Motor Works

    Way Motor Works New Member

    May 4, 2009
    MINI Tuner
    +205 / 0 / -0
    I really like the NM tubes, that's why we custom do them in black. We noticed throttle responce improvement the most.

Share This Page