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Custom Cold (?) Air Intake Build

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iso100

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Thread Starter #21
Edit to the edit: Here are my numbers after a full third-gear pull-
I just realized your peak Airflow Mass was 17.79 while mine was 21.89. I think that's a statistically significant difference (23.05% increase).
 


dyn085

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#22
I need to do some research into what each value represents. You can see my min/max in my screenshot, and through a full third-gear pull the lowest filter pressure I had was 14.09. I also find it odd that I only read a high of 17.79 lb/min mass considering that I've seen higher numbers on both your intake setup and Ryst's, and he just has the paper filter installed. I would think I should fall somewhere between the two.

Fwiw, many CAI's on the market are misrepresented. To be a true CAI it must pull air from outside of the engine bay. Besides OEM, I've only seen one from Mountune and one for the euro models that are available for the FiST. Everything else is a warm air intake and is setup similar to yours in the fact that the element is open within the bay.
 


dyn085

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#23
I just realized your peak Airflow Mass was 17.79 while mine was 21.89. I think that's a statistically significant difference (23.05% increase).
Exactly, but go look at one of Ryst's logs in the datalog thread. Iirc, he is also pulling in the low 20/21's. It doesn't make sense to me.

Maybe I'll swap filters tonight and pull a couple of logs to see...
 


OP
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Thread Starter #24
I need to do some research into what each value represents. You can see my min/max in my screenshot, and through a full third-gear pull the lowest filter pressure I had was 14.09. I also find it odd that I only read a high of 17.79 lb/min mass considering that I've seen higher numbers on both your intake setup and Ryst's, and he just has the paper filter installed. I would think I should fall somewhere between the two.
Agreed. I don't really understand what the pressure number is indicating but if the sensor is between the turbo intake and the filter then it's most likely looking for a vacuum reading (something less than 14.7) beyond a threshold to indicate a clogged or dirty filter. More vacuum means less flow. Again, this is just a guess though.

I also think the lb/min reading will be wildly different based on the temperature (density) of the air coming in... so there's that variable as well. Most of the logs published don't have an intake air temperature variable and that's where we'd be able to tell. Charge temp, yes, but not intake temp.

Fwiw, many CAI's on the market are misrepresented. To be a true CAI it must pull air from outside of the engine bay. Besides OEM, I've only seen one from Mountune and one for the euro models that are available for the FiST. Everything else is a warm air intake and is setup similar to yours in the fact that the element is open within the bay.
Agreed. I think CP-E is working on one as well but again with a metal box and COBB's unicorn will have a metal box but a plastic induction tube.

For the record my plan was to nearly completely seal off the filter from the engine air. I will need to get on production of at least a minimal heat shield sooner rather than later though. These temps are nuts.
 


OP
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Thread Starter #25
Exactly, but go look at one of Ryst's logs in the datalog thread. Iirc, he is also pulling in the low 20/21's. It doesn't make sense to me.
Was just looking at that. With his charge temps starting at 71.6 and climbing to 95 after a 3rd gear pull, I'm betting it was pretty cold, like 65 degrees. That would explain the density. Perhaps I need to figure out a way to adjust airflow mass so that they all read based on a constant corrected intake air temperature.
 


dyn085

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#26
Agreed. I don't really understand what the pressure number is indicating but if the sensor is between the turbo intake and the filter then it's most likely looking for a vacuum reading (something less than 14.7) beyond a threshold to indicate a clogged or dirty filter. More vacuum means less flow. Again, this is just a guess though.

I also think the lb/min reading will be wildly different based on the temperature (density) of the air coming in... so there's that variable as well. Most of the logs published don't have an intake air temperature variable and that's where we'd be able to tell. Charge temp, yes, but not intake temp.



Agreed. I think CP-E is working on one as well but again with a metal box and COBB's unicorn will have a metal box but a plastic induction tube.

For the record my plan was to nearly completely seal off the filter from the engine air. I will need to get on production of at least a minimal heat shield sooner rather than later though. These temps are nuts.
Yeah, it is ridiculously hot and humid here currently. I've noticed that, generally speaking, my charge temps start around 8? higher than what my display reads as ambient in any given log. I'll swap filters tonight and grab some data to see what differences there are/aren't between the two. I'm pretty sure there's a selection for intake temp so I'll grab it as well.

If anything we'll figure out the data through comparison and process of elimination...
 


BlueBomber

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#27
Sooo... how about that heat shield?

You're basically doing what I would do to re-engineer the Injen kit for max cool air. Good work, interested to see it with heat shield fitted.
 


OP
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Thread Starter #28
Sooo... how about that heat shield?

You're basically doing what I would do to re-engineer the Injen kit for max cool air. Good work, interested to see it with heat shield fitted.
I need to mock it up with cardboard then flatten it out and transfer to the ABS sheet before cutting and then forming with a heat gun. I hope to make some progress on Saturday.

I will be attempting to 3D print the factory airbox shock fittings as well but I'm waiting on my digital calipers to arrive (tomorrow) to start modeling.
 


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Thread Starter #29
I 3D modeled my own factory airbox mount nipples so my new heat shield will use the factory shock mounts. It was actually a bit of a pain in the ass to model these things.

My friend will print them out on his 3D printer. The hole in top is set up for a #8 machine screw.



I won't be able to 3D model the shield so my next step there is to do a cardboard mockup that will be transferred to the ABS sheet for cutting and bending.
 


MOFiST

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#30
Are you still running the OEM intercooler iso100?
Charge air temps are post intercooler and I was wondering whether FMIC heat soak factors into your figures as well.
 


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#31
Your set up looks great. Congrats on being original. I'm definitely interested as Blue is to see what happens once you add the heat shield. Keep up the good work
 


Sourskittle

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#32
If your talking about the mass air meter readings, something to think about its that the stock sensor is calibrated to the stock tubes inside diameter. So... If you changed the tube diameter to a bigger tube, the sensor is still cal to the smaller size. That is why mustangs of the past had different sized mafs, but the ecu had to be cal to the maf.

Now... I maybe wrong, but something to think about.
Hope you guys understand what I'm saying, lol.
 


OP
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Thread Starter #33
Are you still running the OEM intercooler iso100?
Charge air temps are post intercooler and I was wondering whether FMIC heat soak factors into your figures as well.
Yes. Still the stock IC for now. I might have misspoke as I was testing and logging the IAT's here but looking at Charge temps for shits and giggles.

If your talking about the mass air meter readings, something to think about its that the stock sensor is calibrated to the stock tubes inside diameter. So... If you changed the tube diameter to a bigger tube, the sensor is still cal to the smaller size.
I understand. Luckily I kept the diameter identical and the USDM cars are not MAF tuned. The ECU doesn't even read the MAF data other than temperature. It's the ones for the rest of the world that are MAF tuned.

Your set up looks great. Congrats on being original. I'm definitely interested as Blue is to see what happens once you add the heat shield. Keep up the good work
Thanks! The heat shield is getting closer!







Of course it's raining now so I can't complete the install.
 


Sourskittle

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#34
I know the ecu does not care, i just meant for your personal readings for air flow. I think its a cool tool. Like if you ported the head or upgraded the turbo (wink) you'll be able to see a increase in mass air, even if the ecu doesn't use it.

But since you kept it the same, all bets are off :)

Where did you get the adaptor? Do they have bigger sizes ? I wonder if I could use something off a different ford car (like a mustang) that uses the same style maf... Then the readings would be off, but... The ecu wouldn't care :)
 


razorlab

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#35
If your talking about the mass air meter readings, something to think about its that the stock sensor is calibrated to the stock tubes inside diameter. So... If you changed the tube diameter to a bigger tube, the sensor is still cal to the smaller size. That is why mustangs of the past had different sized mafs, but the ecu had to be cal to the maf.

Now... I maybe wrong, but something to think about.
Hope you guys understand what I'm saying, lol.
The USDM is SD based and what you are talking about is MAF based.
 


Sekred

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#36
I know the ecu does not care, i just meant for your personal readings for air flow. I think its a cool tool. Like if you ported the head or upgraded the turbo (wink) you'll be able to see a increase in mass air, even if the ecu doesn't use it.

But since you kept it the same, all bets are off :)

Where did you get the adaptor? Do they have bigger sizes ? I wonder if I could use something off a different ford car (like a mustang) that uses the same style maf... Then the readings would be off, but... The ecu wouldn't care :)
FYI

MAF

http://www.treadstoneperformance.co...pter+Pipe,+Nissan,+FORD+and+GM,+Hitachi+Style
 


OP
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Thread Starter #38


Temporary bracket and 3d printed mount. I need to revise the mount and will likely fabricate an entire mount from the 3D printer. This was just so I can get back on the road again. I also need to fab a bracket for the front of the shield.

Does anyone know if the factory airbox air inlet in the grill is a high-pressure ram-air intake or if it's just a neutral-pressure location for the engine to get fresh, cooler air from?

With a shield and wide open bottom I don't want to bother fabricating a plenum from the stock location into the shielded area if it's just neutral pressure. That means it won't do anything. On the other hand, if it is pressurized when driving at speed, then it would help to force in more fresh air and it might be worth doing.
 


Sekred

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#39
Neutral fresh air, draws from a cavity that is formed when the bumper is in position if you can understand that description.

OEM CAI.jpg
 


OP
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Thread Starter #40
Neutral fresh air, draws from a cavity that is formed when the bumper is in position if you can understand that description.
Perfectly understood. Thanks! You just saved me some more fabrication time.
 


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