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Discussion Starter #1
well you know how people have all these different issues with their intakes and fluctuating power reports? and now that X has come out with his new system that actually performs the way an intake should, i began thinking about a few small overlooked issues with many intakes.
- the two hoses that run into the intake are before the MAf. one is some sort of bleeder for the coolant to bleed out air i think, and the other is a part of the crankcase pressure exhaust system. SO, the big hose from the valve cover is open to the inside of the motor allowing air to be expelled and vacuumed out so to speak. well since this hose is before the Maf, this air being drawn into the intake is technically un-metered air.
- i'm wondering if the placement of this line on after-market systems has any negative effects? and, if we were to vent that hose to the atmosphere and plug that inlet to the intake, would we see better AF ratios/more throttle response/more power since ALL of the air coming into the motor is now being accounted for?

Just a few thoughts i was wondering about while daydreaming in calc2. LOL. Discuss.
 

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iv wondered this my self.

What intake are you running, I havnt had a chance to dyno my Comptech setup yet and im wondering what effects the Fujita has on power vs. the stock intake or other CAI's.
 

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Discussion Starter #4
^I threw that poo-jita away. i'm using an X style intake now. and i noticed that on my 03 crv tube, the crankcase hose is practically on the throttle body, and with the crap-jita, it was in a totally different spot.
-we cant run the pcv hose into the end of the filter because oil would contaminate the maf, so i'm thinking "oil catch can-then vent to air".

i just know that with many other maf or AFM monitored vehicles, if you so much as put a pinhole in the intake and didnt have it metered the car would run much worse. obviously thats not our case cuz it came like that, but i think we could benefit from doing it my way. Where are X and Greg tonight? LOL
 

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:popcorn:
 

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it has to do with emissions. the reason why u want to keep them attached and i would assume why some things dont get carb approved. crankcase ventilation is that large hose and i forgot what that smaller one was for...and i was just under my hood today putting in my etd...thats only part of it. theres way more but i dont want to give wrong info. i need to reed my school notes again. ill try to get back at it if noone else gives proper anwer.
 

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Discussion Starter #10
^ i know it has to do with emissisons. its there to aid in the relief of crankcase pressure. thats not the ?. the question is if we can benefit from better monitored airflow by blocking that inlet off.
 

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well, its not just pressure, hydrocarbons (fuel persay) get past the rings into the crankcase and thats whats really being vented. thats what allows for an ever slightly better fuel economy. in short, i dont think performance is hindered, but i believe it could be ever so slightly. thats prolly best i can do for ya.
 

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The key is teh A/f Strategy of the car. And that is what needs to be taken into account. The additional air from the fin trimming is what leans out the A/F and I think that is what makes the power, somehow tricking the MAF, but I haven't looked into it enough, I will and get back with more on thise theory shortly...
 

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The 2 hoses are:
1) air bypass valve...a thermal valve on the front of the motor (next to runner number 4 that allows air to circulate to the engine around the maf based on engine temp. The valve is a melting wax style actuator that works when the engine gets hot enough to melt the wax and expand... same way a termostat works.
2) a pcv (pos crank vent) hose that brings the combustion that leaks past the rings and the oil-rich contents it brings with it from passing through the crankcase. Generally the problem is that anything leakage past the rings ends up back in the engine taking up space that a good combustable mixture could occupy, thereby robbing some power. But the more important issue is that the fumes from the crankcase actually cause the mixture to become more knock sensitive... thereby reducing your octane rating in a way, which is why alot of guys running hi boost supercharged/turbo cars run it to atmosphere. But doing that is very bad for emissions because I've seen enough blowby on a big hp turbo car with a well worn motor to blow out a candle at 10 ft from the valve cover port.

It's the knock sensitivity thing that is the biggest concern for power, but I don't recommend it for a daily driver because you are fubarring greenhouse gases that keep our planet cool. Be a good citizen for our children. :)

Chris at RedShift
 

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Discussion Starter #15
^ok. but would we benefit from the air being totally accounted for from the maf if that hose wasnt allowing the throttle body to draw in air before it could get metered? i guess thats my main question. i'm not too worried about emissions since i live in florida.
 

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No, definitely don't plumb it before the maf. You'll make it dirty and oily and it won't meter correctly. Since the blowby it's generates is known, you can easily tune for it. Stock setup is this way too; so it's already tuned for it.
Chris at RedShift
 

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Discussion Starter #17
i think yoou're mistaken me here chris. i'm talking about if i ran that hose to the back of the car far away from the intake alltogether, not putting any into the intake. and the pcv is not for blow-by. its to alleviate the counter pressure generated under the pistons from combustion. if you have a sealed container and push the piston down, it will create pressure underneath now. thats why its pcv(positive crankcase vent).
 

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uh.. that's not exactly correct. ;) .... you have 2 pistons going up and 2 going down. The motion of the pistons nets nothing. It's the blow-by of combustion past the rings that pressurizes the crankcase. if you think 100 psi from a compression test can blow by, try 10x that during combustion. And you can dump these fumes from the crankcase to atmosphere, but it's not emissions friendly obviously. :)
Chris
 

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Discussion Starter #19
^that is very true also about the blow by, i just thought you meant that was ALL it was for, my bad. and if that hose was removed, we still have the one with the pcv valve on it doing a decent amount of pcv evacuation.
-anyone else have any input on if we can see better ratios and more power from measuring all the air instead of letting some be unaccounted for?
We should let X test this out since he has simple access to a dyno.:biggrin:
btw, thanks for your responses so far chris.
 
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