The K&N oil is petroleum based. aFe oil is not. AFE oil is very different and causes much less problems related to the oil coming off of the filter/getting on the MAF sensor.
Motordyne doesn't either and wants real people dynoing his stuff. Real people don't lie, manufactures will. Real people show his stuff making more power than others. There's something to be said for a manufacturer that doesn't gloat.
yeah 'real people' to conduct scientific tests on flow rate and efficiency haha
The longer tubes most likely have nothing to do with it.
Better flowing cone filters, pipes air in from outside car. Short rams that were COMPLETELY shielded like the factory airboxes should work just as well, but there's really nothing like that.
Bigger diameter tubes (with MAF sensor re-calibration to allow for the difference in voltage readings) should make more power, but I was under the impression that the Stillen's were OEM diameter (I could be mistaken on this...)
luigi90210
11-02-2013 01:54 AM
Quote:
Originally Posted by Mandingo
(Post 2549748)
Oh I like sciencey threads. This old physics relation shows what many of us already know from experience or intuition:
Resistance (R) is directly proportional to the length (L) of the tube and viscosity of the fluid (a constant in this case obviously). R is inversely proportional to the radius to the 4th power.
So as length increases, resistance increases (we know this already). What isn't as obvious is that as radius of the tube increases, resistance decreases dramatically.
Of course we need more complicated math (computer models) to see how turbulence is created by bends in the tube and how that affects resistance. The flow through the filters could even be explained by the above relation in a sense, but it would require calculus and lots of data we can't get.
Basically, the large area of the K&N filters used on the Gen3 overcomes the negative effect of having longer tubes (I think their radius is a little larger than stock as well? correct me if I'm wrong). The lower IAT due to the filter location is not what gives the noticeable power increase. The difference in temperature between the stock draw location and the Gen3 location is too small to affect air density enough. Perhaps the computer is responding to the lower temperature readings and making adjustments that translate to more power?
iirc the stillen uses 90 degree mandrel bends and that reduced flow by 30% which is the equivalent to trying to flow air through 3ft of additional piping(at least this is what i know for intercoolers on turbo cars, it might be worse for N/A cars)
the reason stillen intakes make more power over stock is it is tricking the ECU by mechanically leaning it out(like all intakes except for AEM) so the computer will only read X amount of air when there is really X+Y air(Y being the additional air not accounted for), and that combined with the cold air and better flow account for the rest of the gains
Quote:
Originally Posted by Jordo!
(Post 2551817)
The longer tubes most likely have nothing to do with it.
Better flowing cone filters, pipes air in from outside car. Short rams that were COMPLETELY shielded like the factory airboxes should work just as well, but there's really nothing like that.
Bigger diameter tubes (with MAF sensor re-calibration to allow for the difference in voltage readings) should make more power, but I was under the impression that the Stillen's were OEM diameter (I could be mistaken on this...)
no the stillens are slightly bigger than OEM(OEM is 2.34 i believe stillen is 2.38)
if someone were to modify a stock airbox to fit on a SRI and completely seal it off from the engine bay, in theory it should outperform the long tube intake at speed because it is getting similar temps as the LTI and there is less restriction and in some cases(like fujita intakes), the short rams are physically larger than the long tubes are
EDIT these videos are pretty interesting
DEpointfive0
11-02-2013 02:20 AM
^Mighty car mods... Sorry, those guys are retards...
CAI on an intercooled car almost defeats the purpose, I agree, all you're beating is less restriction... And the other car is a POS
luigi90210
11-02-2013 12:15 PM
Quote:
Originally Posted by DEpointfive0
(Post 2551853)
^Mighty car mods... Sorry, those guys are retards...
CAI on an intercooled car almost defeats the purpose, I agree, all you're beating is less restriction... And the other car is a POS
well it does help out a little bit but in the end you are right, with an intercooler it doesnt matter where you draw the air in from
they have a pod filter episode as well and it shows pod filters dont flow any more than pannel filters
synolimit
11-02-2013 06:24 PM
Quote:
Originally Posted by Jordo!
(Post 2551817)
The longer tubes most likely have nothing to do with it.
Better flowing cone filters, pipes air in from outside car. Short rams that were COMPLETELY shielded like the factory airboxes should work just as well, but there's really nothing like that.
Bigger diameter tubes (with MAF sensor re-calibration to allow for the difference in voltage readings) should make more power, but I was under the impression that the Stillen's were OEM diameter (I could be mistaken on this...)
I don't care about science really. I care about dynos and analysis samples from Joe Shmow. That's good enough for me. I'm making 295/244 untuned. That's good enough for me filter wise. Unless a filter catches more and adds 10hp I'm good with a K&N.
Mandingo
11-02-2013 06:37 PM
Quote:
Originally Posted by luigi90210
(Post 2551836)
the reason stillen intakes make more power over stock is it is tricking the ECU by mechanically leaning it out(like all intakes except for AEM) so the computer will only read X amount of air when there is really X+Y air(Y being the additional air not accounted for), and that combined with the cold air and better flow account for the rest of the gains
I remember reading about this a while back. Wouldn't the leaning-out effect be negated by a tune? The folks that posted before/after dynos showed gains from the G3 intake even after the A/F was corrected with Uprev if I remember correctly.
Honesty
11-02-2013 07:04 PM
The stock intake is not optimized for flow and only flow. It is designed to quiet the sound of intake air and to prevent the vehicle from sucking in water into the combustion chamber.
The reason why aftermarket cold air intakes increase horsepower (which is just flow) is because they have fewer restrictions and allow for a higher amount of cfms to come through the pipe than the factory snorkel/filter. One has a more focused purpose, which it accomplishes.
The length of the tube is overall the same or only slightly longer than the factory intake, but it is straighter, wider, and simpler. As a result, air flows through it more easily. Therefore the vacuum in front of the intake valves draws in more air.
Length isn't the ONLY factor here. The overall design of the factory intake is not optimized for flow. That's the problem.
Rusty
11-02-2013 07:08 PM
I got to laugh at some of the posts on here. Good entetainment. :bowrofl:
Rusty
11-02-2013 07:11 PM
Quote:
Originally Posted by Honesty
(Post 2552672)
The stock intake is not optimized for flow and only flow. It is designed to quiet the sound of intake air and to prevent the vehicle from sucking in water into the combustion chamber.
The reason why aftermarket cold air intakes increase horsepower (which is just flow) is because they have fewer restrictions and allow for a higher amount of cfms to come through the pipe than the factory snorkel/filter. One has a more focused purpose, which it accomplishes.
The length of the tube is overall the same or only slightly longer than the factory intake, but it is straighter, wider, and simpler. As a result, air flows through it more easily. Therefore the vacuum in front of the intake valves draws in more air.
Length isn't the ONLY factor here. The overall design of the factory intake is not optimized for flow. That's the problem.
Hey, someone who got it. ;)
andre12031948
11-02-2013 07:27 PM
Quote:
Originally Posted by Honesty
(Post 2552672)
The stock intake is not optimized for flow and only flow. It is designed to quiet the sound of intake air and to prevent the vehicle from sucking in water into the combustion chamber.
The reason why aftermarket cold air intakes increase horsepower (which is just flow) is because they have fewer restrictions and allow for a higher amount of cfms to come through the pipe than the factory snorkel/filter. One has a more focused purpose, which it accomplishes.
The length of the tube is overall the same or only slightly longer than the factory intake, but it is straighter, wider, and simpler. As a result, air flows through it more easily. Therefore the vacuum in front of the intake valves draws in more air.
Length isn't the ONLY factor here. The overall design of the factory intake is not optimized for flow. That's the problem.
Not going to go into this or that. I just know that with the stock intakes you get ONLY the outside air, and it's somewhat under pressure from beneath the car. Also the stock tubing doesn't get anywhere as hot as the metal ones.
synolimit
11-02-2013 09:25 PM
Quote:
Originally Posted by luigi90210
(Post 2551836)
iirc the stillen uses 90 degree mandrel bends and that reduced flow by 30% which is the equivalent to trying to flow air through 3ft of additional piping(at least this is what i know for intercoolers on turbo cars, it might be worse for N/A cars)
the reason stillen intakes make more power over stock is it is tricking the ECU by mechanically leaning it out(like all intakes except for AEM) so the computer will only read X amount of air when there is really X+Y air(Y being the additional air not accounted for), and that combined with the cold air and better flow account for the rest of the gains
no the stillens are slightly bigger than OEM(OEM is 2.34 i believe stillen is 2.38)
if someone were to modify a stock airbox to fit on a SRI and completely seal it off from the engine bay, in theory it should outperform the long tube intake at speed because it is getting similar temps as the LTI and there is less restriction and in some cases(like fujita intakes), the short rams are physically larger than the long tubes are
EDIT these videos are pretty interesting
Lol the stillen doesn't trick the ecu, AEM does with the electric box they give you which is garbage. Doesn't matter the filter or the pipe size with the stillen, the MAF sees what it sees, period. The stillen isn't bigger or that really matters say you said 0.04" is nothing. Both are 2.5" OD, just depends how thick the material is which will change the ID but not enough to measure MAF scale or HP wise.
Quote:
Originally Posted by luigi90210
(Post 2552170)
well it does help out a little bit but in the end you are right, with an intercooler it doesnt matter where you draw the air in from
they have a pod filter episode as well and it shows pod filters dont flow any more than pannel filters
I agree with it does help coming from a certain point and not with it doesn't matter. If it didn't matter than having the radiator running in the summer would produce the same temps as in the winter. We're only talking about 20-40 degrees maybe difference but you can see big temp swings. Keeping the compressor housings as cool as possible will increase results. A cai even in a turbo car will be better than a sri in the engine bay.
