[TEKSMRT]

Where did you buy the generic pipe pieces?

eBay or Amazon, whatever was cheapest.

 

[ThreeFiveSix]

I ordered the ebay intake. Gonna put something together like this

 

[ThreeFiveSix]

Ok so the Ebay intake came in. I cut a 2" silicone coupling and glued it inside the pipe to reduce the diameter at the MAF. I drove around engine light free for a day so it works. Tonight I went back and measured my stock tube and it is 3".
I was under the impression that the 06-07 models had a slightly smaller maf pipe?
If the both the intake and stock pipes are 3" then the silicone insert should not be needed and is impeding air flow.
Can anyone clarify this info before I rip out the insert only to possibly having to glue it back in again?!?

 

[TEKSMRT]

Ok so the Ebay intake came in. I cut a 2" silicone coupling and glued it inside the pipe to reduce the diameter at the MAF. I drove around engine light free for a day so it works. Tonight I went back and measured my stock tube and it is 3".
I was under the impression that the 06-07 models had a slightly smaller maf pipe?
If the both the intake and stock pipes are 3" then the silicone insert should not be needed and is impeding air flow.
Can anyone clarify this info before I rip out the insert only to possibly having to glue it back in again?!?

I drove my 2009 Rav4 V6 SAP around with the 3" eBay intake and it threw codes left and right. Hasn't thrown a code since I inserted the silicon coupler.

I never did measure the ID of my MAF housing but I probably could.

 

[ThreeFiveSix]

Here's my setup.
Car got written off before I had a chance to really enjoy it.

 

[TEKSMRT]

Here's my setup.
Car got written off before I had a chance to really enjoy it.

Written off? That's too bad... good luck with the Si!

 

[Myxalplyx]

Here's my setup.
Car got written off before I had a chance to really enjoy it.

Sorry to hear of your loss man. That sucks. Like TEKSMRT said, good luck with your Si. If you are on Civicx.com, I go by 'Myx' on there. I have a 2018 EX Hatchback. See you over there. :wink

 

[Myxalplyx]

I drove my 2009 Rav4 V6 SAP around with the 3" eBay intake and it threw codes left and right. Hasn't thrown a code since I inserted the silicon coupler.

I never did measure the ID of my MAF housing but I probably could.

This is interesting. I guess I should've given some input here but I didn't quite understand why what I did resolved the problem. I did have the same issue in a couple of instances. Let me explain!
In these scenarios I always had the 3" maf piping. The only thing that I changed was the 45 degree coupler piece that it connected too.

1) When I connected a 4" 45 degree angled coupler to the 3" maf pipe, I threw a code.
2) When I slid the 3" 45 degree coupler piece 'too much' onto the 3" maf pipe, I threw a code. ***This makes absolutely no sense to me***
So what I did was pull the 3" 45 degree couple away from the 3" maf pipe a little more, clamp and drive. CEL light, stop, pull it out a little more, drive, etc. It was almost as if the coupler piece that was connected to the 3" maf pipe needed to be as long and straight as possible before it hit the 45 degree turn towards the battery. Once positioned right, I had no more CELs for years.

It makes no sense I know but that's how I resolved this issue. It seems like a fluke so I didn't talk much about it and just called it an error on my part. But that was my thinking around it. And somehow it worked. This is on a 2010 though. Perhaps that is different as well.

I only placed an insert inside of a 4" 45 degree coupler that I had attached to the 3" maf sensor piping. I had to do this so I could attach it to the 3" maf sensor piping. That was when I tested the 3" piping connected to a 4" 45 degree bend and 4" pipe all the way down to the foglight. I don't think I reported on how that went. I lost any and all lowend power I ever had and quickly changed back to smaller piping. That's when I tested gradually reducing (Or increasing depending on how you look at it) intake piping. (I know this may all sound confusing). A lot of stuff I tried/tested I don't talk about.

 

[84hachi]

Hi guys, I'm bring this thread back from the dead for a new development regarding the Camry SRI. You can modify the heat shield to fit the RAV4. Just need cut off the protruding bit, drill a new hole, and delete a bracket holding the main engine harness. Later, I'll add another screw, I was dead tired when I finished.

 

[AzzurriAltezza]

hachi inspired me to use my shield that was collecting dust. I cut off the same sections he did, and then when I was figuring out the hole pattern for mounting I thought I could use the spacers from the stock airbox to help. For the stock spacers - 1/2" hole is snug, 9/16" will give a little wiggle room.

When I put it in the engine bay, the shield was resting on the rear cable harness and battery tray mount, so I installed some spacers (3/4") from some spare work stuff. Had to trim a bit more off the shield for the battery tray as well.

The shield was still wobbly on the stock spacers since they are only supporting the center - but if the rubber stop that's included with the intake is used, it really firmed it up. The stud on the top of mine fell out during install, but if yours it intact it's easy to remove.

It was a fun little project and does make the intake setup look more "official", but I'm still not happy with the intake tube length and where the filter sits. I tried putting the Apollo kit in after I did this and there's no room to install the tube adapter at the end of the filter. I think the Camry intake tube length needs to be chopped 1" or so, but even then it will be a tight fit.
I also didn't like that using the shield doesn't allow "easy" use of the intake support bracket (means I'd have to fabricate something), so the intake tube is basically using the grommet in the cutout for support if it shifts a bit.

Going to order the misc parts to relocate the filter where the stock resonator was like the others have done, but I already had all of these parts in the garage so why not

 

[84hachi]

I forgot to update. I took a piece of leftover metal and drilled a hole dead center making a makeshift splice plate that fits over the open space and utilizes the forward factory air box hold down thread.

Overall air filter choice is still up in the air. After months of research my choice will most likely be the Apexi Power Intake filter.

No oil and really good hp gains. The MKIV Supra forum peeps did massive research with many filters. Apexi stands as the best to them and in the Skyline groups

http://www.mkiv.com/techarticles/filters_test/2/index.htmlbkbk

But, that will come much later, I'm back to focusing onto suspension.

 

[DL175]

I forgot to update. I took a piece of leftover metal and drilled a hole dead center making a makeshift splice plate that fits over the open space and utilizes the forward factory air box hold down thread.
View attachment 152497

Overall air filter choice is still up in the air. After months of research my choice will most likely be the Apexi Power Intake filter.
View attachment 152498
No oil and really good hp gains. The MKIV Supra forum peeps did massive research with many filters. Apexi stands as the best to them and in the Skyline groups

http://www.mkiv.com/techarticles/filters_test/2/index.htmlbkbk

But, that will come much later, I'm back to focusing onto suspension.

The filter is sucking in hot air. The ideal setup is to draw in cold air from under the car. There is only one place to get cold air and that is on the driver side just behind the front bumper.

 

[84hachi]

The heat shield has taken care of some heat. Temperature of air going into the front of the filter at wot is currently at 76 degrees. I duct taped digital thermometer to the front of the filter when I did it. Others have done it this way and are happy about it. I am too.

 

[AzzurriAltezza]

So while I was shopping for the various pipes and couplings, I came across an intake tube that looked like it might work. It had a 45, a straight section, and 80ish final bend. I figured if it didn't work as a whole, I could chop it up and use the parts and would come out to be less than buying the parts individually.

The intake is from a 98-03 4cyl Honda Accord Amazon.com: 3" Intake Pipe Perfit formance Cold Air Intake Induction Kit With Filter fit for Honda Accord DX/LX/EX/SE 1998 1999 2000 2001 2002 2.3L(black): Automotive
First thing I did was lay it in the engine bay to get an idea how it would sit:

I then chopped the first elbow off that had the vacuum tube, which left me with a single 3" pipe. After chopping and removing my heat shield, I could see how the end section would sit with a filter:

Now I put the Camry intake back on and then attached the Accord intake with a 3" coupler

I still had the support bracket on the Camry section, but the additional weight of the Accord section didn't give me the warm & fuzzies since the inlet area was resting on a cable & frame. The Accord intake came with a straight metal piece, so I made a bend and used an existing hole from the stock snorkel to mount the new bracket. Put a few scrap pieces of heat shield insulation (from the Camry intake kit) on it so it wasn't metal on metal.

Installed everything and used a few tie wraps to secure the inlet to my bracket. The entire intake is pretty sturdy and nothing is rubbing, so I'll check on it after a week or two and make sure that doesn't change.

Sound wise it's definitely louder than just the Camry intake. Over 5k at wot was great...not quite GS350 intake great , but really good for a grocery getter!! I'm still using the garbage filter that came with the Camry intake, so once I put a K&N on there it should be good to go. I don't expect to feel any power gains (although on my test drive with the cool air tonight it felt great from a roll!) as the setup doesn't seem optimal for hp, but it's better than stock and should keep the iat lower than the Camry intake.

If I were to do it again: I'd purchase matching finishes & materials of the intakes, create a good inlet support bracket, and fabricate a shield that blocks off the engine bay from the filter - keeping the filter more isolated to using air in the fender/bumper area.
Parts summary:
07-11 Camry V6 Intake ($40-50)
98 Accord 2.3L Intake ($40-50)
3" Silicone coupler and clamps ($10)
Quality air filter/optional ($30-50)

 

[TEKSMRT]

So while I was shopping for the various pipes and couplings, I came across an intake tube that looked like it might work. It had a 45, a straight section, and 80ish final bend. I figured if it didn't work as a whole, I could chop it up and use the parts and would come out to be less than buying the parts individually.

The intake is from a 98-03 4cyl Honda Accord Amazon.com: 3" Intake Pipe Perfit formance Cold Air Intake Induction Kit With Filter fit for Honda Accord DX/LX/EX/SE 1998 1999 2000 2001 2002 2.3L(black): Automotive
First thing I did was lay it in the engine bay to get an idea how it would sit:

I then chopped the first elbow off that had the vacuum tube, which left me with a single 3" pipe. After chopping and removing my heat shield, I could see how the end section would sit with a filter:

Now I put the Camry intake back on and then attached the Accord intake with a 3" coupler

I still had the support bracket on the Camry section, but the additional weight of the Accord section didn't give me the warm & fuzzies since the inlet area was resting on a cable & frame. The Accord intake came with a straight metal piece, so I made a bend and used an existing hole from the stock snorkel to mount the new bracket. Put a few scrap pieces of heat shield insulation (from the Camry intake kit) on it so it wasn't metal on metal.

Installed everything and used a few tie wraps to secure the inlet to my bracket. The entire intake is pretty sturdy and nothing is rubbing, so I'll check on it after a week or two and make sure that doesn't change.

Sound wise it's definitely louder than just the Camry intake. Over 5k at wot was great...not quite GS350 intake great , but really good for a grocery getter!! I'm still using the garbage filter that came with the Camry intake, so once I put a K&N on there it should be good to go. I don't expect to feel any power gains (although on my test drive with the cool air tonight it felt great from a roll!) as the setup doesn't seem optimal for hp, but it's better than stock and should keep the iat lower than the Camry intake.

If I were to do it again: I'd purchase matching finishes & materials of the intakes, create a good inlet support bracket, and fabricate a shield that blocks off the engine bay from the filter - keeping the filter more isolated to using air in the fender/bumper area.
Parts summary:
07-11 Camry V6 Intake ($40-50)
98 Accord 2.3L Intake ($40-50)
3" Silicone coupler and clamps ($10)
Quality air filter/optional ($30-50)

Awesome! I'm impressed at how well that Honda intake works with all the necessary needed bends for the Rav4. Nice job and great ingenuity!!

 

[SoNic67]

It makes no sense I know but that's how I resolved this issue.

It actually makes sense. For example, I installed Smoke Detectors in HVAC ducts and always the instructions say to allow for lengths of straight duct (6 duct diameters) before the sensor, to avoid stratification and "quiet" the flow.

 

[RB Suibian]

I installed a short ram intake similar to 84Hachi installed above for performance purposes. The IATs are really bad and I am trying to decide which direction to go next (back to stock-ish or CAI to behind fog light), BUT before I proceed I have a question for everyone (i hope someone can answer it!):

I am getting Long Term Fuel Trims (LTFTs) of -10.9 and -15.6 at idle, -13.3 and -10.9 at 3500 rpms. A/F is 14.6-14.7 while idling and 15.4 at 3500 rpms. Under load (while driving), all the readings change but its still negative 4-15% Generally, negative LTFTs are the computer's reaction to a RICH condition that was detected by the Oxygen sensor. I believe a RICH condition is being detected due to the installation of the Short Ram Intake (SRI). The SRI changes the way the column of air flows inside the intake.

Here is what I found on this:
According to the Wilhelm guys (link to their research here, read the first bit on variations in the airflow due to a velocity stack or lack thereof), the MAF reads the air entering the intake at the center of the incoming column of air and not the outside near the inside of the piping. The standard OEM air box design (with the straight tube and no velocity stack) creates a column of air inside the intake that has a faster velocity at the center and a slower velocity at the periphery near the inside of the intake piping. So, with the OEM air box the MAF reads a high mass of air and the whole system (ECU, etc.) is setup at this higher rate and adjusts the system based on this higher flow rate or g/s. So, when you add a SRI or Cold Air Intake with a velocity stack, according to their research, the velocity stack and, alternatively, perhaps a reducer, create a column of air in the intake that is uniform in velocity across the whole section of the pipe. This is a good thing for performance because more air gets in the intake overall at uniform rate but it may have negative side effects. With the use of a velocity stack or a reducer at the intake opening, the air moves into the intake uniformly but the air in the center of the column of air is at a lower speed than what is normally detected in a stock air box. As a result, the MAF measures a lower reading with the SRI setup when compared to the reading in a stock air box.

So, what happens next in the engine management system is what I get utterly confused about! Does the computer, as a result of reading less air then reduce the amount of fuel? And thereby squirt less fuel by creating negative STFTs and negative LTFTs because it is reading a RICH condition (because less air is detected at the MAF)? Or does something else happen? The LTFTs are used to adjust the amount of fuel injected into the engine so that the engine stochiotic-something-or-rather balance at 14.7:1, right? So, the LTFT are a good thing and I don't need to worry about them right? Just leave it be and keep usin the SRI or another CAI with a velocity stack? No worries?

I am, admittedly, a NOOB when comes to the engine management systems aspect of cars but I am learning. Any instruction would be very helpful!

Can anyone chime in and let me know I am thinking through this scenario properly or not? Also, will having LTFTs cause any reliability issues or damage? Poor gas mileage? I guess if I understood the situation correctly, is going back to the stock OEM air box or getting a tuner to program my ECU the only way to eliminate the LTFTs? Do I need to eliminate LTFTs?

Thanks in advance!

 

[SoNic67]

Does the computer, as a result of reading less air then reduce the amount of fuel?

Yes, the ECU reads the air and based on internal tables squirts fuel to what he "thinks" are appropriate levels. Then, if is in closed loop, the O2 sensors actually measure the burning products and, if there is any unused O2 left, the ECU adjusts (trims) the short term values from the default table. Long term trims are derived from the short term trims and stored.
Note that are many regimes where the loop is open, because the O2 sensors cannot react that quickly. Then the ECU uses the factory tables adjusted with the long term trims (best guess). Open loop happens:

• Start-up/warm-up. The engine isn’t trying to optimise for anything here other than warming up — much like using a choke on simpler engines or older motorcycles.
• Medium throttle/acceleration: The engine needs more fuel and isn’t optimising for efficiency any more.
• Deceleration (Engine braking): The engine RPM isn’t constant, even if the throttle is (it might even be held off).

So if you have negative LTFT, in closed loop you are fine, but in open loop... I don't know. There is an upper limit of those adjustment trims that will trigger a CEL.
Note that the actual value of O2 sensor on our cars is not just an on-off switch, like on older sensors, they are "wideband O2 sensors" that output a proportional voltage.

Good explanation (even if is for motorcycles, applies to any engines): Open Loop vs Closed Loop: Understanding Fuel Injection
And wideband: What is a Wideband Oxygen Sensor?

 

[RB Suibian]

Yes, the ECU reads the air and based on internal tables squirts fuel to what he "thinks" are appropriate levels. Then, if is in closed loop, the O2 sensors actually measure the burning products and, if there is any unused O2 left, the ECU adjusts (trims) the short term values from the default table. Long term trims are derived from the short term trims and stored.
Note that are many regimes where the loop is open, because the O2 sensors cannot react that quickly. Then the ECU uses the factory tables adjusted with the long term trims (best guess). Open loop happens:

• Start-up/warm-up. The engine isn’t trying to optimise for anything here other than warming up — much like using a choke on simpler engines or older motorcycles.
• Medium throttle/acceleration: The engine needs more fuel and isn’t optimising for efficiency any more.
• Deceleration (Engine braking): The engine RPM isn’t constant, even if the throttle is (it might even be held off).

So if you have negative LTFT, in closed loop you are fine, but in open loop... I don't know. There is an upper limit of those adjustment trims that will trigger a CEL.
Note that the actual value of O2 sensor on our cars is not just an on-off switch, like on older sensors, they are "wideband O2 sensors" that output a proportional voltage.

Good explanation (even if is for motorcycles, applies to any engines): Open Loop vs Closed Loop: Understanding Fuel Injection
And wideband: What is a Wideband Oxygen Sensor?

Thanks for that info. Yea, that makes sense regarding closed loop and open loop. But if i run an SRI or CAI and have negative LTFT like I am will have any long term effect such as poor gas mileage or engine wear etc.?

 

[SoNic67]

The long OE duct makes the flow laminar, more uniform, so the punctual measuring of airspeed by MAF resistor is an adequate approximation.

The fact that the modded air flow is not as expected, to me raises the alarm that at certain regimes the indicated value can be different from actual amount of air flow by variable amounts. Like at idle we can have a smaller deviation and at wot have a bigger deviation. Or something in between, turbulent flow is unpredictable. The LTFT is just an average of all those, so it will not perfectly compensate at all rpms and engine loads when using the different intake.
Shorted stacks lead to turbulent flow, and that's in-predictable. A straight length of few diameters is needed to calm the air flow.

My personal opinion is that the short air intake are worthless on stock cars. In majority of cases they suck in hotter air (less dense) from inside the hood.

Even when the air dam is done properly (even your link has the CAI sucking hot air from engine bay), they gain a bit of power at WOT. But without a custom cam profile, they cannot add significant power to the engine at other regimes (besides WOT) and they affect negatively the fuel consumption.
That's because the cam profile (overlapping) was set at design stage by having a certain air flow resistance at both intake and exhaust. Reducing those will increase the passage of unburned fuel to exhaust. VVTi custom programming can help, but this requires a lot of testing.
Remember that unburned fuel is also bad for cats, it will damage them in short time.