I just picked up a fujita intake, first thing i noticed is how small it looked. So i measured the inner diameter of the stock intake and of the fujita. I couldnt believe what i saw, take a look...
The fujita intake has an inner diameter of around 2.5 inches, while the stock intake has an inner diameter of around 2.875 inches.
When you do the math, the stock intake area is 6.5 sq inches while the fujita's is 4.9 sq inches. The fujita intake is 25% smaller then the stock intake.
How on earth can the maf accuratly measure the air now? The area that it sits in passes 25% less air then the stock intake.
I cant believe that a company that specializes in intakes f@#$ed up like this, its insane. If the gxp wouldnt have a wideband o2 sensor the car probably wouldnt be driveable since the airflow is miscalculated.
so maybe its not the K&N filter that was at fault after all?
__________________ 2007 'Cool' GXP
Personal Audio Link
Custom/Homemade A-Pillar Pod w/ Boost/Vac Gauge
Dejon IC Pipes & CAI
Wastegate Rod Mod
Solo Street Race
Debaged
Both the k&n and non oiled filters throw check engine lights, so its not the filter.
But this size difference definetly does not help, im not putting this intake on my car. Fujita should come out with a proper 3" pipe like everyone else and replace these free of charge.
Both the k&n and non oiled filters throw check engine lights, so its not the filter.
But this size difference definetly does not help, im not putting this intake on my car. Fujita should come out with a proper 3" pipe like everyone else and replace these free of charge.
I've been using their CAI for 10,000 miles and have not had any problems.
I just picked up a fujita intake, first thing i noticed is how small it looked. So i measured the inner diameter of the stock intake and of the fujita. I couldnt believe what i saw, take a look...
The fujita intake has an inner diameter of around 2.5 inches, while the stock intake has an inner diameter of around 2.875 inches.
When you do the math, the stock intake area is 20.4 inches while the fujita's is 15.2 inches. The fujita intake is 25% smaller then the stock intake.
How on earth can the maf accuratly measure the air now? The area that it sits in passes 25% less air then the stock intake.
I cant believe that a company that specializes in intakes f@#$ed up like this, its insane. If the gxp wouldnt have a wideband o2 sensor the car probably wouldnt be driveable since the airflow is miscalculated.
the diameters of the tube and the raise at which air passes the sensor are totally independent of each other. the one intangible you did not mention is although the pipes is smaller the restriction towards the nose of the car is severely decreased by comparision to the stock air box, ergo reguardless of the diameter air flow increases dramatically. look at it like this.
if you have a funnel with a 12 inch cone, and a 1 inch expelling aperture, it will not releasing its contents as fast as a funnel with an 8 inch cone and 3 inch expelling aperture.
its a rough comparision but the dynamics are similar
my car goes into limp mode every other time. Its not the filter since I replaced it.
__________________
TEAM FREAKY CIRCUS S**
Every available Option including On*Star
2.5" Stubby Black Antenna
Lil' Chromies
Solstice License Plate Frame (not really a mod)
Norms Fenders
Holes in front bumper from plate bracket (custom)
Solo Hi Flow Cat/ 3in dual exhaust
Kappa Intake
[quote=jag767;507181]the diameters of the tube and the raise at which air passes the sensor are totally independent of each other.
The rate or velocity of the air anywhere in the inlet pipe is completely dependant on the diameter of the tube regardless of where you measure the velocity in the tube. The velocity of the air in a 2.5" diameter tube has to be greater than the velocity of the same mass of air passing through a 2.875" diameter tube.
If you are using a hot wire MAF sensor the single is a function of the velocity of the air passing over the sensor. If the velocity is greater than originally designed for you ECU is being told by the MAF that more air is being drawn into the engine than there actually is. Can't be good, it's got to screw up the ECU's logic to some degree.
Shabby your right there is a 25% difference in tube area but the areas are 4.9 vs 6.5 sq. inches.
So between small tube diameter, funky bends that provide turbulent airflow, poor MAF mounting location fit/finish, and not actually providing a cooler air supply... why are we putting these on our cars again? lol
I have no personal experience with the Fujita, but I have plenty with the Werks
K&N or Dryflow, I think the oiled filters are getting a bum rap.
I am starting to think these products were rushed to market before any proper testing was done... I think there was a couple places that gave you a couple days to send it back... ugh huh.
Yes, Yes, Yes I know... there are those of you out there that are not having a single issue with yours.
Just because there were people that had Yugos or Ford Pintos, and lived problem free didnt mean they were not crap.
I have yet to hear anything bad about the Dejon CAI (cept no mounting bracket - which was solved) but time will tell. Let us hope that they got it right.
All I have to say is Buyer Beware
__________________ Team Solstice 2008
MEAN GXP with the works, minus smoker, pedals, XM, Big Brother, and Onions
Current AAT topless outing record -8 degrees F
the diameters of the tube and the raise at which air passes the sensor are totally independent of each other.
The rate or velocity of the air anywhere in the inlet pipe is completely dependant on the diameter of the tube regardless of where you measure the velocity in the tube. The velocity of the air in a 2.5" diameter tube has to be greater than the velocity of the same mass of air passing through a 2.875" diameter tube.
If you are using a hot wire MAF sensor the single is a function of the velocity of the air passing over the sensor. If the velocity is greater than originally designed for you ECU is being told by the MAF that more air is being drawn into the engine than there actually is. Can't be good, it's got to screw up the ECU's logic to some degree.
Shabby your right there is a 25% difference in tube area but the areas are 4.9 vs 6.5 sq. inches.
i disagree. if you take a straw thats 1 inch in diameter and another hose thats 1.25 inches with half the opening restricted naturally it will not have the flow of the smaller straw even though it is larger.
i disagree. if you take a straw thats 1 inch in diameter and another hose thats 1.25 inches with half the opening restricted naturally it will not have the flow of the smaller straw even though it is larger.
The thing you're missing is the speed of the air at different points in the system. In a fat area, air will be moving slowly, while in a narrow portion, air will be moving more quickly.
Bottom line is: If the MAF is in a tube that's smaller than the stock location, air must travel past it at a higher velocity, fooling the computer into thinking more air is entering the motor than actually is (since it thinks that high velocity is in a larger tube). This could easily throw a code since the MAP sensor and MAF sensor are not agreeing with each other.
I have no personal experience with the Fujita, but I have plenty with the Werks
Hey at least your werks intake is of proper dimensions
Quote:
Originally Posted by jag767
i disagree. if you take a straw thats 1 inch in diameter and another hose thats 1.25 inches with half the opening restricted naturally it will not have the flow of the smaller straw even though it is larger.
Have you seen what people do to the gm v8 mafs on the camaro/vette? They port the outside wall for more flow at the expense of running a bit leaner. Once you change the dimensions of the area where the maf sits you mess up the maf's ability to calculate the proper amount of air.
Im willing to bet that whoever has a fujita intake on their gxp that their fuel trims are on the negative side.
Quote:
Originally Posted by ERuff
Shabby your right there is a 25% difference in tube area but the areas are 4.9 vs 6.5 sq. inches.
I knew something was off, i just dont see 20 sq inches on the intake. Thanks for the fix
