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Old 11-03-2012, 09:09 AM   #1
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ps, i defer to jaykay on the rough pipe; mech eng trumps eng phys when it comes to fluid dynamics.

also a quick caveat on those agency or evo-style cold air intakes. to actually be 'cold air' intakes, they have to completely seal against the side of the engine compartment and the engine compartment lid. otherwise, the engine can and will draw air from inside the compartment and this air is MUCH hotter than outside air. the poor fit of most of these units is what has given them a bad name in many circles.

the other thing to note is that they come with the housing for the mass airflow sensor (maf). this unit sends a reading of unit airflow to the cars computer. the computer then takes this reading and multiplies it by the diameter of the housing within which the maf sits to determine volume of airflow which is essential to calculate how much fuel to inject. if you change the diameter of the maf housing without reporgramming, the computer will be doing bad math. 2.5 and 3.2 liter engines have maf housings with different diameters. if you look at most aftermarket cold air intakes, they use the same maf housing for all engine types (check it out, the same product number for 2.5 and 3.2 engines) so you really affect your computers ability to adapt.

Last edited by The Radium King; 11-03-2012 at 09:22 AM.
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Old 11-03-2012, 05:39 PM   #2
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Quote:
Originally Posted by The Radium King View Post
ps, i defer to jaykay on the rough pipe; mech eng trumps eng phys when it comes to fluid dynamics.

also a quick caveat on those agency or evo-style cold air intakes. to actually be 'cold air' intakes, they have to completely seal against the side of the engine compartment and the engine compartment lid. otherwise, the engine can and will draw air from inside the compartment and this air is MUCH hotter than outside air. the poor fit of most of these units is what has given them a bad name in many circles.

the other thing to note is that they come with the housing for the mass airflow sensor (maf). this unit sends a reading of unit airflow to the cars computer. the computer then takes this reading and multiplies it by the diameter of the housing within which the maf sits to determine volume of airflow which is essential to calculate how much fuel to inject. if you change the diameter of the maf housing without reporgramming, the computer will be doing bad math. 2.5 and 3.2 liter engines have maf housings with different diameters. if you look at most aftermarket cold air intakes, they use the same maf housing for all engine types (check it out, the same product number for 2.5 and 3.2 engines) so you really affect your computers ability to adapt.
Hey TRK,

Love the math! Thought the ram air was "fishy" but couldn't put my finger on it. 215mph?

The suction in the fender well is a good point. My attempt thus far has been (3rd attempt) to design a "box as round as possible that is sealed" for that EXACT reason. The only way you get better cold air is to seal the source. Would like to see what the King is mackin'. Post pics when you can.
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Last edited by Homeboy981; 11-04-2012 at 04:11 AM. Reason: spelling
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