Cleaned MAF, idle problem

[cody]

Aw, I see. My air box is sealed to the fender.

[ddub]

I'll buy the air box off of you Sperry. I nervous to get a CAI because I won't be getting a tune for a while. Also, it would be a pain in the but to change your filter. I was also looking at another short ram like the SPT.

[sperry]

Originally Posted by ddub

I'll buy the air box off of you Sperry. I nervous to get a CAI because I won't be getting a tune for a while. Also, it would be a pain in the but to change your filter. I was also looking at another short ram like the SPT.

Lemme make sure I can find it... it's buried in the garage somewhere. I'll PM you.

[Bajozzy]

http://forums.nasioc.com/forums/show....php?t=1388916

[ddub]

Thanks for the link, i'm PM'ed him to buy it.

Does anyone have any experiance with a CAI and a stg2 AP map? Will my car run bad or can the ECU compensate? I found both good and bad experiances on nasioc.

[cody]

I wouldn't risk it, personally. Even if you go with an intake that uses the stock MAF tube inside diameter, the turbulence profile is different.

[sperry]

Originally Posted by ddub

Thanks for the link, i'm PM'ed him to buy it.

Does anyone have any experiance with a CAI and a stg2 AP map? Will my car run bad or can the ECU compensate? I found both good and bad experiances on nasioc.

Chances are, there's already a filter in my air box if you're still planning on buying it. Unfortunately, I get home from work at midnight these days and have to be back at 8am, so I haven't had time to poke around the garage, and I'll be out of town thursday/friday. But I might be able to get it to you tonight or this weekend.

PM me your phone number?

[dayofpain]

aps or bust.

its the only and i mean the ONLY cai that was researched for a decent ammount of time that reacts JUST like the stock airbox but makes more power.

[Bajozzy]

I would reccommend getting the car tuned after any CAI.

[dayofpain]

aps, dont need a tune. cant stress it enough.

[ddub]

First i'm gonna get the stock air box from Sperry, later i'll look into getting a CAI.

[Bajozzy]

Originally Posted by dayofpain

aps, dont need a tune. cant stress it enough.

I disagree . If tuning is a precise balance of Air, Fuel, Timing and Boost and the APS or any inlet affects the airflow or air/fuel mix in any way (less restriction, different turbulance, signifacantly more air flow ect..) then a Tune would be beneficial in my opinion. I am not a tuner, and dont claim to KNOW anything but I think your wrong. Sure, you can put it on your car and hope for the best, but to say "dont need a tune. cant stress it enough" is a stretch.

[dayofpain]

nope, ill say it again.

dont need a tune. cant stress it enough.

you CAN get a tune after removing enough weight from the dam car. or perhaps changing the spark plugs or a pulley.

the subaru computer is an amazing piece of work, it can and will adapt to quite alot and most people dont give it near enough credit.

and btw from what i understand the reason that the aps is so unique is because it flows EXACTLY like the stock box, meaning that changing the air fuel mix isnt required.

the reason it gains power is because it pulls different temperature air (which is easily measured and compensated for by the stock ecm). or at least thats what i read when it first came out in 2001.

people are way to quick to say "go get tuned" at every single piece of crap they throw on their car. its sickening that SOME tuners have brainwashed the entire community into thinking that.

im not saying im perfect but i got all of two pro tunes EVER, and i had a ton of parts come on and off my car. im sure i was missing out on a whole 5-6 hp for whole months at a time. sucks for me i guess.

[sperry]

Put it this way: if you change parts on the car, regardless of what they are, the car will run better and make more power with a good custom tune on it. Even if the X CAI is "safe" without a tune, the car is better with a tune. In fact, the car is probably going to be better with a custom tune and *no* parts than it is with a stock tune and no parts.

[dayofpain]

Originally Posted by sperry

Put it this way: if you change parts on the car, regardless of what they are, the car will run better and make more power with a good custom tune on it. Even if the X CAI is "safe" without a tune, the car is better with a tune. In fact, the car is probably going to be better with a custom tune and *no* parts than it is with a stock tune and no parts.

i believe its the degree that everyone attributes the word need to that i dont like.

[Dean]

Originally Posted by dayofpain

nope, ill say it again.

dont need a tune. cant stress it enough.

you CAN get a tune after removing enough weight from the dam car. or perhaps changing the spark plugs or a pulley.

the subaru computer is an amazing piece of work, it can and will adapt to quite alot and most people dont give it near enough credit.

and btw from what i understand the reason that the aps is so unique is because it flows EXACTLY like the stock box, meaning that changing the air fuel mix isnt required.

the reason it gains power is because it pulls different temperature air (which is easily measured and compensated for by the stock ecm). or at least thats what i read when it first came out in 2001.

people are way to quick to say "go get tuned" at every single piece of crap they throw on their car. its sickening that SOME tuners have brainwashed the entire community into thinking that.

im not saying im perfect but i got all of two pro tunes EVER, and i had a ton of parts come on and off my car. im sure i was missing out on a whole 5-6 hp for whole months at a time. sucks for me i guess.

The only way a power mod without tune could be truly safe is if it was indistinguishable from the previous part. If that is the case, then why do it?

An intake mod can do one of three things at a given point. Provide a larger, smaller or equal MAF voltage for a given volume of air. While the ECU can deal with these in closed loop, it has no control in open loop to fix a problem. If it is rich, no big deal unless it is extreme, but if it is lean, this can be a problem. A little lean may improve performance on a stock car, but add two or three mods that cause even a little leanness or one big lean mod and you could be in KABOOM territory.

I'd also be hard pressed to believe there is a significant temperature difference between the fender and the stock intake with snorkus and even if there is, intake temperature is basically meaningless on a forced induction engine with any form of intercooler.

The bottom line is if you make any engine/power mod without tuning, at least take the time to do some logging to see what effect it has.

[dayofpain]

Originally Posted by Dean

I'd also be hard pressed to believe there is a significant temperature difference between the fender and the stock intake with snorkus and even if there is, intake temperature is basically meaningless on a forced induction engine with any form of intercooler.

it does. dont have to explain it, the engineers did that research not me. ALSO if you start at Y temperature and dont change the turbo or intercooler you get X temperature at the head. than you install a CAI which changes Y -10degrees it almost directly translates to X-10degrees. its not rocket science. if the middle of the thermal equation is the same than its really easy to change the ends of it. it always takes the same ammount of energy within a given range to manipulate temperature.

and for the dam record. subaru owners are the ONLY owners in large numbers that believe the fallacy of needing to be tuned under every circumstance. mits owners dont buy it. porsche owners dont buy it. honda owners for sure dont buy it. why do subaru owners? because most of the boards are controlled by tuners and their loyal followers that are in it to make money.

people need to get over the dam fact that you need a tune for every dam part you add.

i ran normal stage 2 map for over 2 years. i had a front mount, cai, twin vent bpv, no cat, headers, turbo inlet and probably some shit im forgetting. I had the car "checked up on" (IE datalogged) and it was fuckin fine.

you buy shitty parts then yeah im sure your car needs a tune cause the RD by the no name brand consisted of "DANG thats a big filter! lets stuff it in the fender!". quality parts cost money for a reason. listen to the maker of said parts when youre asking yourself if you need a tune. end of story. yeah you can chase that last 3-4 horsepower and lie to yourself to the point where you are spending 200 dam dollars for a tune after installing a new sparkplug just cause you are scared. but ill bet you a free tune that ill wind up with more power and a shitton less money spent. not to mention not a single problem.

[100_Percent_Juice]

damn, its spelled damn.

[ddub]

I agree. I have read, in some cases, that people have thrown cel codes and had rough running conditions with a APS CAI during idle. There have been some good reviews, but I personally don't like throwing any codes. In my case, my short ram intake was most likely creating to much turbulance at idle, which did not allow the mass air flow sensor to detect the correct amount of air flowing by. However, during normal driving conditions, the MAF sensor detected a correct reading and gave near perfect air/fuel ratios. I'm sure the APS works great during normal driving, but not so well at idle. In the case of turbulance, there isnt any way of correcting this, unless you are able to manipulate the air fuel. I'm sure a UTEC could do this.

[Dean]

Originally Posted by dayofpain

it does. dont have to explain it, the engineers did that research not me. ALSO if you start at Y temperature and dont change the turbo or intercooler you get X temperature at the head. than you install a CAI which changes Y -10degrees it almost directly translates to X-10degrees. its not rocket science. if the middle of the thermal equation is the same than its really easy to change the ends of it. it always takes the same ammount of energy within a given range to manipulate temperature.

Sorry, it doesn't work that way. it is the heat of compression that is the significant contributor to Charge Air Temperature, not intake temperature in a forced induction motor. I don't have the time to go find a reference, but this has been discussed and proved ad nauseum.

[Bajozzy]

Everyone has probably read this but here is the link to the intake FAQ

http://forums.nasioc.com/forums/show...40&postcount=1

Do intakes cause problems with the air/fuel ratio? Many seem to believe that since their XXX intake does not cause a CEL or exhibit any driveability problems, then their XXX intake must be good. Though the apparent increase in power gives them peace of mind, what they don't take into account is their intake is actually causing unseen harm to their engine. This is generally due to two reasons:
1. The intake piping diameter is incorrect. This can cause a lean condition in the case of larger than stock diameter piping or a rich condition with decreased diameter piping.
2. The air flow is not laminar. The stock piping, through it's apparent unusual design, is constructed to smooth out turbulent air flow. Aftermarket systems do not take this into consideration. When turbulence occurs, the MAF sensor will suddenly see more or less air then it had previously. This will cause the ECU to respond by making the engine run leaner or richer for as long as the error from turbulence occurs.

Can the intake problems be corrected through aftermarket engine management? Yes. There are a wide variety of engine management systems that have the capability of modifying the mass air flow values to correct intake piping that is non-OEM size. Some intakes have especially troublesome turbulence problems. Since this turbulence can occur at different points in the power band, based on both engine RPM and engine load, all that can be done to make the engine run safely is to recalibrate the engine with a relatively rich overall tune to compensate.

[dayofpain]

Originally Posted by Dean

Sorry, it doesn't work that way. it is the heat of compression that is the significant contributor to Charge Air Temperature, not intake temperature in a forced induction motor. I don't have the time to go find a reference, but this has been discussed and proved ad nauseum.

sorry man, but every link and literally everything i have read on thermodynamics including a college professor with which i have had this exact conversation is exactly how i described it. y-10 != x-10 but its relatively close. so close in fact that there is constant variable used for which i cannot find atm.

[Dean]

Originally Posted by dayofpain

sorry man, but every link and literally everything i have read on thermodynamics including a college professor with which i have had this exact conversation is exactly how i described it. y-10 != x-10 but its relatively close. so close in fact that there is constant variable used for which i cannot find atm.

I said intake temp is insignificant not that it doesn't contribute something. Even 20 degrees in intake temp is pretty small compared to 200, 300 or more degrees of compression and turbo heat. And with an intercooler, unless it is heat saturated, it is really the determining factor of charge temp anyway. If you want to reduce intake temp, get a better intercooler, not a CAI.

[sperry]

Originally Posted by dayofpain

sorry man, but every link and literally everything i have read on thermodynamics including a college professor with which i have had this exact conversation is exactly how i described it. y-10 != x-10 but its relatively close. so close in fact that there is constant variable used for which i cannot find atm.

If you have a good intercooler, it's not X-10 != Y-10, it's X cooled to ambient == Y cooled to ambient, in which case, a CAI makes no difference.

Whether or not anyone's IC's are that good is the question... probably not so much on a hot day, but on a hot day, you're going to be losing power anyway so what's the difference of losing 10hp vs 12hp... is not really significant.

[cody]

Originally Posted by SteveM

Here is a cool calculator for you guys to play with. The site has a metric buttload of turbo information.

Link

Steve