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Does colder intake charge really work on Dyno?

  1. Aug 17, 2011 #1
    Hello, I got a question on auto engines. especially on Naturally Aspirated engines.

    I know that colder intake = more oxygen in the mixture, then the ecu will compensate that with more fuel, etc, etc, more power... But colder air will also result to less efficient atomization of fuel, reduced flame front speed which has the effect of retarding timing which can reduce torque or neutralize the effect of denser charge...

    But generally speaking, could it really result to greater output across the rev range? Does lower manifold temperature really work or is just hype to sell aftermarket mods?
  2. jcsd
  3. Aug 17, 2011 #2
    Yes, cooler air temperatures result in more brake horsepower.

    However, many aftermarket "cold air" kits add power mostly by leaning out the factory air/fuel ratio (kits with a new mass air meter) and a lower restriction air filter and duct work rather than reducing the temperature of the air inlet. Most newer cars already draw air from the fenderwell.
    Last edited: Aug 17, 2011
  4. Aug 17, 2011 #3
    Thanks Edge.

    I'll guess I did the right thing. I thought I'm just saving money. I've basically left the intake tract factory stock but wrapped them in insulating tape, used paper intake manifold gasket and bypassed throttle body coolant. I've also rerouted the inlet to a ram scoop I've made myself that's completely sealed off the engine bay and gets incoming air directly.

    I thought it's just in my head that the car felt more powerful - which used to feel weaker when the engine reaches operating temps or if the weather is hot. Now it seems to be peppy regardless of outside temps.
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