Why metallic intakes do not work

[Cjymiller]

Originally Posted by IceFyre13th

The MAF is rock steady, STFT and LTFT are between 5% to -5% running or stopped. Gas mileage has gone from 31.7 MPG to 35.5 MPG average. Its only been on a week, and I hope everything stays this way...........

First, what is STFT and LTFT?

Second, those MPG gains are huge! I'm definitely a sucker for MPG. Why do you think this is? Is this something that is exclusive to the TRD intake because of the larger filter surface area?

[IceFyre13th]

Originally Posted by Cjymiller

First, what is STFT and LTFT?

Second, those MPG gains are huge! I'm definitely a sucker for MPG. Why do you think this is? Is this something that is exclusive to the TRD intake because of the larger filter surface area?

STFT= Short term fuel trim

LTFT= Long term fuel trim

Why do I think the gas mileage is better, the engineers who designed the TRD intake have vast amounts of money and time to do it right.....not to mention the equipment / tools to test and research the results......

[PERRIN_Jeff]

Sorry for the long post, and while this may help competitor intake sell, its important to say. Also to the OP, I am not trying to argue just point out my own findings over the years.

First variable is your Unichip.
Where are the correction factors programmed? Meaning, during Unichips tuning, did they see your intake running 10% rich under full throttle, then they removed 10% across the board? Or did they only change the correction where it was different? During our testing and tuning of cars and different intakes, I have NEVER seen one that has the same correction needed at low RPM, Mid RPM and high RPM. If the Unichip was tuned for the intake you have, then for 100% you would NEVER get CEL. My guess is that it wasn't properly calibrated.

Grounding Concerns
In my years of making and playing with intakes, weather raw, powdercoated, plastic aluminum or steel, I have NEVER seen them being metal and grounding out cause anything. On this car specifically we tested a separate MAF housing connected to a silicone coupler (fully isolated MAF). This allowed us to test things quickly. After the design was settled, the solid "RAW" piece was bolted to the car and it performed the same way, indicated by the AFR under full throttle and trims at light load.

The MAF sensor is grounded internally which connects back to the chassis. Even the signal wire is shielded by the ground. IF the flange actually touches the circuit inside it HAS to be grounded to it. Even then it won't matter as its all the same ground. If anything this will help make for a better clearer signal. I can say for 100% that the intake being grounded out, isn't an issue.

Intakes and "Turbulance"
The most important thing to understand is ALL INTAKES HAVE "TURBULENCE". Even the stock air box isn't perfect and it requires a specific calibration for the box. Subaru has used the same basic MAF housing since 2008. It's plastic, has an ID of 2.75", and has air straighteners, yet both the 08 WRX's and BRZ have different MAF curves. This is because air is entering them slightly different and have different curves after the MAF. This all affects how they work.

During all our testing we made a MAF housing like you mentioned and it was VERY VERY lean. In fact we have made this same housing (2.75"ID) on both the STI and BRZ and in both case they cause the car to run very lean. These were both short ram types without bends in front of them eliminating other variables to start with. I made an adjustable MAF housing just to be able to test different sizes on the fly and In all situations, I found that in order to run the car safely and as close to the same AFR as stock it needs to be much smaller. The other factor is the bends. Tighter bends, bigger bends and how close they are to the MAF affect the AFR and in different parts of the RPM. There is a reason why our intake is the way it is. It doesn't throw CEL's, the trims are in line with what we want, and it make some power.

Intakes NEED a Tune
Far too often do I hear intakes are all the same. I hate hearing that as that is not the case at all. Really what this comes down to is that a lot of intakes require a tune and some should have a tune and very few don't need a tune. Technically even our intake needs a tune to have it match the OEM's EXACT AFR curve. But it doesn't NEED a tune as the changes to the AFR are not enough to cause a CEL, or cause a loss in power. I feel 100% confident that our intake with the stock tune runs safe, makes power and NEVER throws a CEL.

For those looking to make the maximum power (versus just a little HP and some cool sounds) the only way to get that is by tuning your car to your intake. We know that there are customers who just want a good bolt on and don't want a tune, so we made our normal intake. Then there are the guys who want the most power and understand they need a tune, which is why we made our 3" intake system.

So before everyone starts freaking out about intakes, you need to know more about the intake you are using.

- Does is throw a CEL? If so, which one?
- If its a P0172 then its a good chance that it NEEDS a tune.
- Does it run lean under full throttle?
- If you have a tune for an intake and you get a CEL (related to AFR or intake) then the tune isn't calibrated properly for the intake.
- If designed properly HEAT isn't an issue. Even if the metal tube is 200F the actual air that touches this and heats up isn't going to heat up anywhere near 200F, and even then is a such a tiny amount it doesn't effect HP.
- Metal vs plastic doesn't have an affect on the grounding of the sensor.
-Does it have proven HP with Proven AFR curves?

Hopefully this helps everyone with choosing an intake and while it would be great if it was ours, that is not the purpose of the post. This is a post for everyone to help understand intakes better.

[qoncept]

Originally Posted by IceFyre13th

My first thought was the heat issue. The intake was ceramic coated, also I tried intake wrap, a reflective insulating wrap claimed to reduce temps by 30% or more. Stopped temps did drop, moving temps would start out lower, but after a few miles the 10 F over outside air would be the norm.

The problem with this is that the intake isn't heating the air appreciably. When you're at a stop you're just sucking in hot air from the engine bay.

[FR-S Matt]

Originally Posted by IceFyre13th

@FR-S Matt You are wrong, not saying who anyway.......but please stop guessing, and please don't turn this into a Vendor bashing thread.

Yes the original one showed issues using SolidWorks Flow Simulation.......even my optimized design still had some, there is no way to make a perfect flow in a automotive environment.

I think the original and mine would work fine, but there has to be a way to isolate the MAF sensor from an unintentional ground.......that is all!!!! It has everything to do with the metal intake causing the unintentional ground.....

Tuning via UniChip or Flash Tuning is only really needed after this to get the most out of the modifications.....not to correct poor flow, but to tune the combination. Like I just said, there is no way to make a perfect flow in a automotive environment.

I'm not turning this into a vendor bashing thread. I've used a metallic intake, Perrin specifically, and had 0 issues. Granted I'm no engineer, but that intake is very smooth and I am not sure what temps it runs.

[IceFyre13th]

@PERRIN_Jeff First, Thank you for your insight........I will confirm it was not yours, because you took the time to help me and others get to the bottom of the issue I brought up.

Originally Posted by PERRIN_Jeff

First variable is your Unichip.
Where are the correction factors programmed? Meaning, during Unichips tuning, did they see your intake running 10% rich under full throttle, then they removed 10% across the board? Or did they only change the correction where it was different? During our testing and tuning of cars and different intakes, I have NEVER seen one that has the same correction needed at low RPM, Mid RPM and high RPM. If the Unichip was tuned for the intake you have, then for 100% you would NEVER get CEL. My guess is that it wasn't properly calibrated.

I can not say anything on what is or is not "tuned" in the UniChip tunes. I do know the custom tune I had for the intake I had built from my redesign of the original on I purchased was the best for the few months it ran without problems.

I did remove the UniChip from my car, as I stated in the first post....I should have been more clearer than saying "it ran worse".......the same wild MAF readings and bad LTFT and STST happened when it was off. The main issue while off was how bad it idled and accelerated, these issues were corrected with my custom tune the first time.

Originally Posted by PERRIN_Jeff

Grounding Concerns
In my years of making and playing with intakes, weather raw, powdercoated, plastic aluminum or steel, I have NEVER seen them being metal and grounding out cause anything. On this car specifically we tested a separate MAF housing connected to a silicone coupler (fully isolated MAF). This allowed us to test things quickly. After the design was settled, the solid "RAW" piece was bolted to the car and it performed the same way, indicated by the AFR under full throttle and trims at light load.

The MAF sensor is grounded internally which connects back to the chassis. Even the signal wire is shielded by the ground. IF the flange actually touches the circuit inside it HAS to be grounded to it. Even then it won't matter as its all the same ground. If anything this will help make for a better clearer signal. I can say for 100% that the intake being grounded out, isn't an issue.

On this issue, I found the tabs are electrically connected to one of the five pins the MAF sensor has.....I do not know what the pin is connected to electrically on the vehicle.

I can say that even if it were a ground connection as well, even though they are both ground this can sill cause what is known as a ground loop that can make electronics "freak out" ((look what a ground loop can do to audio circuits in car stereo, (one of my first engineering jobs was in car audio)). So not in all cases would this "help make for a better clearer signal". Most times ground loops cause bigger issues than "star" or a single point grounding a system.

I do not doubt your findings though, my vehicle is not the same one you tested on and there very well could be other variables that make the issue I found more apparent. If you were close to me I would volunteer my car for you to prove or dis-prove my claim. I am open to the possibility what I perceive as the issue is wrong.

Originally Posted by PERRIN_Jeff

Intakes and "Turbulance"
The most important thing to understand is ALL INTAKES HAVE "TURBULENCE". Even the stock air box isn't perfect and it requires a specific calibration for the box. Subaru has used the same basic MAF housing since 2008. It's plastic, has an ID of 2.75", and has air straighteners, yet both the 08 WRX's and BRZ have different MAF curves. This is because air is entering them slightly different and have different curves after the MAF. This all affects how they work.

During all our testing we made a MAF housing like you mentioned and it was VERY VERY lean. In fact we have made this same housing (2.75"ID) on both the STI and BRZ and in both case they cause the car to run very lean. These were both short ram types without bends in front of them eliminating other variables to start with. I made an adjustable MAF housing just to be able to test different sizes on the fly and In all situations, I found that in order to run the car safely and as close to the same AFR as stock it needs to be much smaller. The other factor is the bends. Tighter bends, bigger bends and how close they are to the MAF affect the AFR and in different parts of the RPM. There is a reason why our intake is the way it is. It doesn't throw CEL's, the trims are in line with what we want, and it make some power.

We are both in 100% agreement, it is impossible to create perfect turbulence free intake tracks in an automotive (or other) applications.

I appreciate the additional information you provided on the testing of your intake. I actually learned why the original intake was designed the way it was now.

Originally Posted by PERRIN_Jeff

Intakes NEED a Tune
Far too often do I hear intakes are all the same. I hate hearing that as that is not the case at all. Really what this comes down to is that a lot of intakes require a tune and some should have a tune and very few don't need a tune. Technically even our intake needs a tune to have it match the OEM's EXACT AFR curve. But it doesn't NEED a tune as the changes to the AFR are not enough to cause a CEL, or cause a loss in power. I feel 100% confident that our intake with the stock tune runs safe, makes power and NEVER throws a CEL.

For those looking to make the maximum power (versus just a little HP and some cool sounds) the only way to get that is by tuning your car to your intake. We know that there are customers who just want a good bolt on and don't want a tune, so we made our normal intake. Then there are the guys who want the most power and understand they need a tune, which is why we made our 3" intake system.

So before everyone starts freaking out about intakes, you need to know more about the intake you are using.

- Does is throw a CEL? If so, which one?
- If its a P0172 then its a good chance that it NEEDS a tune.
- Does it run lean under full throttle?
- If you have a tune for an intake and you get a CEL (related to AFR or intake) then the tune isn't calibrated properly for the intake.
- If designed properly HEAT isn't an issue. Even if the metal tube is 200F the actual air that touches this and heats up isn't going to heat up anywhere near 200F, and even then is a such a tiny amount it doesn't effect HP.
- Metal vs plastic doesn't have an affect on the grounding of the sensor.
-Does it have proven HP with Proven AFR curves?

Hopefully this helps everyone with choosing an intake and while it would be great if it was ours, that is not the purpose of the post. This is a post for everyone to help understand intakes better.

I did not intend on making anyone "freak out" on what I found to be the cause of my intake issues, my only intent (and why I refuse to say who the first one was from, notice I still think their design is sound as well) was to show what I perceive as an issue and possible explanation as to why so many others claim the factory intakes work better with a drop in filter.

My car is not the same is your car, not built the same time yours was, not the same color, might not have the same mods......etc. etc....

The only thing I did find was when either my metallic intake, or the first metallic one I bought, and saw where the paint had rubbed through the mounting point effectively grounding the MAF sensor unintentionally was replaced by a full plastic one that isolated the MAF sensor did my issue seem to go away and my MAF, LTFT, and STFT readings seem to be rock steady compared to the other intakes I have used.

Again, thank you for taking to time to explain your side, hopefully we can all benefit from each others findings.

[Urmyson]

Originally Posted by PERRIN_Jeff

Then there are the guys who want the most power and understand they need a tune, which is why we made our 3" intake system..

I haven't seen Your 3in intake, has it been released yet?

[IceFyre13th]

Originally Posted by qoncept

The problem with this is that the intake isn't heating the air appreciably. When you're at a stop you're just sucking in hot air from the engine bay.

Only if the intake gets its air from that area...........not the case here.

[sosick]

Bro the ez fix or test to ur theory would be to un ground that support arm. Rubber between metal and use zip ties as the bolt. N if nothing changed then ur wrong about the maf getting grounded. If u would have tesedt this then u wouldnt have to make a guess on y u think they dont work. Now I think about it y didnt u try that? U wrote this whole this about it being grounded but u never ungrounded the damn thing. I kinda feel dumb after reading this.

[sosick]

Originally Posted by Chee-Hu

It's a pretty simple solution, sir. Don't purchase metallic intakes?

No one is actually testing that so for u guys to say dont buy that kind. Doesnt even make since

[sosick]

Originally Posted by IceFyre13th

@FR-S Matt You are wrong, not saying who anyway.......but please stop guessing, and please don't turn this into a Vendor bashing thread.

Yes the original one showed issues using SolidWorks Flow Simulation.......even my optimized design still had some, there is no way to make a perfect flow in a automotive environment.

I think the original and mine would work fine, but there has to be a way to isolate the MAF sensor from an unintentional ground.......that is all!!!! It has everything to do with the metal intake causing the unintentional ground.....

Tuning via UniChip or Flash Tuning is only really needed after this to get the most out of the modifications.....not to correct poor flow, but to tune the combination. Like I just said, there is no way to make a perfect flow in a automotive environment.

What do u mean there is no way? Do u know what rubber is? Or plastic? Maybe u need to buy that first intake system u first bought and make some rubber gaskets then make some zip ties then test ur theory. Arent u some kind of engineeer of some sort? How can u not think of that

[sosick]

@ PERRIN

notto thread jack but are ur claims of hp gain without or with a tune.

[s2d4]

Hit it with a hammer?

[IceFyre13th]

Originally Posted by sosick

Bro the ez fix or test to ur theory would be to un ground that support arm. Rubber between metal and use zip ties as the bolt. N if nothing changed then ur wrong about the maf getting grounded. If u would have tesedt this then u wouldnt have to make a guess on y u think they dont work. Now I think about it y didnt u try that? U wrote this whole this about it being grounded but u never ungrounded the damn thing. I kinda feel dumb after reading this.

Two reasons, the intake goes through the radiator support and could ground there, the throttle body touches the intake tube. I have no way to be sure the tube is not connected to ground elsewhere.

I have tried something else though tonight and reading your question, now that it is totally isolated I ran a wire to the tabs on the MAF sensor to the area I thought the bolt was grounding the intakes to...........ready for it, it wigged out again like before with the aluminum intakes. Removed my "artificial ground" just created and back to running right......