CAI or no CAI???

[Wrinkled_Donut]

RHO has stock CAI already, but if you want you can spend $400-$700 on filter in different color that will do absolutely nothing )

This 100%. I'll never understand peoples need to modify literally every single thing. Reminds me of the Honda fast & furious crowd when I was in high school in the early 2000's. Granted those were awesome times- but If you want to do anything worthwhile, just add boost with a tuner. Exhaust if you want more noise. Everything else (performance wise, until you start talking BIG hp) is literally a waste of $$ with modern turbo engines.

 

[Adub]

Research these claims for us @Dbiznez1

Track Series Carbon Fiber Cold Air Intake System w/ Black Pro 5R Filter

Designed from the ground up for the RAM 1500 RHO, the aFe POWER Track Series Air Intake System delivers uncompromising performance, cutting-edge materials, and factory-level fitment. This intake is purpose-built to unlock the full potential of your high-output Hurricane engine with increased...

afepower.com

 

[Dcchris311]

Research these claims for us @Dbiznez1

Track Series Carbon Fiber Cold Air Intake System w/ Black Pro 5R Filter

Designed from the ground up for the RAM 1500 RHO, the aFe POWER Track Series Air Intake System delivers uncompromising performance, cutting-edge materials, and factory-level fitment. This intake is purpose-built to unlock the full potential of your high-output Hurricane engine with increased...

afepower.com

So from what ive seen, I went from a consistent 20psi with the afe filter to 22psi through out the rpm range after installing my intake. A local member will also be testing it once im doing working the kinks, along with a set of downpipes. Im not talking about the ~28psi spike, thats only momentary.

I have since added a Cat6 and now im seeing 24psi consistently through out the rpm range.

 

[RamFan]

So from what ive seen, I went from a consistent 20psi with the afe filter to 22psi through out the rpm range after installing my intake. A local member will also be testing it once im doing working the kinks, along with a set of downpipes. Im not talking about the ~28psi spike, thats only momentary.

I have since added a Cat6 and now im seeing 24psi consistently through out the rpm range.

How does one get more boost from an air cleaner and tube when the computer controls the boost?

Chris

 

[INTIMD8R]

How does one get more boost from an air cleaner and tube when the computer controls the boost?

Chris

Less restriction in the air filter and with smoother tube, will force more air into the intake creating more boost.

 

[Dcchris311]

Less restriction in the air filter and with smoother tube, will force more air into the intake creating more boost.

Bingo!!

 

[Faze]

yea that doesn't make much sense, I'm thinking his ECU just switched to different map..

CAI design might be fooling the MAF sensor, the ECU thinks you getting less air than you actually are, but then the O2 sensor measures it's actually running lean, adds more fuel.. there's your increase of boost, but should be also controlled by MAP sensor, so shouldn't be all across the RPM's

 

[Dcchris311]

Bingo!!

I'll be doing some dragy pulls and datalogging this week.

yea that doesn't make much sense, I'm thinking his ECU just switched to different map..

CAI design might be fooling the MAF sensor, the ECU thinks you getting less air than you actually are, but then the O2 sensor measures it's actually running lean, adds more fuel.. there's your increase of boost, but should be also controlled by MAP sensor, so shouldn't be all across the RPM's

Yeah, at first I didnt understand how I'd gain an additional 2psi so I went to ChatGPT it explained how it's possible. Im going to blank out certain words as im still developing the CAI. But it's essentially what @INTIMD8R said in his post.


ChatGPT:

That +2 psi gain is actually very plausible, and here’s why it happens with an intake like yours:


---

1. Reduced Restriction at the Filter

*Paragraph was removed*

Increased the effective filter area feeding the intake.

*Removed*

*Removed*


That efficiency lets the turbos pull air in with less effort, which directly translates into a higher manifold pressure.


---

2. Improved Compressor Efficiency

Turbos don’t “make” boost out of nothing; they compress what they can draw in. If the inlet is restrictive, the compressor works harder, generates more heat, and may hit flow limits sooner.
*Removed*

The compressor map point shifts slightly (more airflow at a given shaft speed).

The turbo doesn’t need to spin as high to hit a target boost → sometimes the ECU allows more headroom before wastegate duty caps it.

Result: observed boost rise.



---

3. Pressure Ratio vs. Flow Balance

Think of boost as resistance to airflow. By reducing restriction at the intake side, you’re improving the balance of the whole system (compressor → intercooler → intake manifold). The system can move more CFM for the same effort. That often shows up as a higher peak boost reading under load, even without a tune change.


---

4. Heat and Density Effects

Lower restriction → cooler intake temps before compression. Cooler air entering the turbo is denser, so when compressed to the same target pressure, it yields slightly more manifold pressure (and mass flow). That’s often seen as 1–2 psi more boost on the datalog.


---

In short: your intake isn’t artificially adding boost—it’s letting the turbos operate more efficiently, so the engine can achieve a slightly higher pressure and flow under the same control strategy.

 

[Faze]

I can't re-confirm that from what you wrote but ok please tell Chatgpt that the engine you talking about is a Hurricane Engine with MAF, MAP and torque request model ECU, twin turbo with wastegate, I think what you wrote was like for Diesel engines or some mechanical turbo engines without electronics to regulate

 

[Dcchris311]

I can't re-confirm that from what you wrote but ok please tell Chatgpt that the engine you talking about is a Hurricane Engine with MAF, MAP and torque request model ECU, twin turbo with wastegate, I think what you wrote was like for Diesel engines or some mechanical turbo engines without electronics to regulate

It's aware that im talking about the RHO, I have recall memory currently on, so I can just start asking questions regarding this and it automatically knows that im talking about the RHO.

Here's the response to your question.

Great question — and yes, it does matter whether the RHO’s boost control strategy is MAP-only or MAP + MAF, because it changes how the ECU interprets your intake change.


---

1. MAP (Manifold Absolute Pressure) Regulation

If the ECU is controlling boost purely based on MAP, then it will try to hit a target manifold pressure regardless of intake changes.

In this case, your intake shouldn’t give you extra boost pressure unless:

The ECU’s boost control strategy has headroom (not tightly closed-loop).

The wastegate duty cycle map isn’t limiting spool at higher flow.


What you’d normally see is less wastegate duty needed to hit the same boost → meaning the turbo works more efficiently, runs cooler, and makes more mass flow at the same psi.



---

2. MAF + MAP Combination

If the RHO uses both MAF (Mass Air Flow) and MAP:

The MAF sensor directly measures incoming airflow mass.

When restriction is reduced, the ECU sees more airflow at the same throttle opening → and depending on how the torque request tables are set up, it may allow the turbos to build slightly more boost before wastegate duty cuts in.

This is why you might actually see a 1–2 psi rise in the datalog, because the ECU isn’t capped strictly by MAP alone.




---

3. Why You Saw +2 psi

The most likely explanation:

The ECU uses MAF for load calculation and MAP for boost safety, not strict closed-loop MAP control.

Your intake reduced restriction, so airflow rose → ECU permitted more boost until either torque limits or MAP limits were approached.

Hence, the datalog showed ~+2 psi higher than before.




---

Bottom line:
If it were MAP-only, you’d usually just see more efficient turbo operation (same boost, lower WGDC).
Since the RHO uses both MAF + MAP, your intake change translated into actual higher observed boost because the ECU is airflow-responsive, not purely boost-capped.

 

[Dark Knight G45]

If an air filter swap or the intake tube swap (or a combo) created an actual turbo spool noise with 0 hp gain, I would do this in a heartbeat. But what I’m worried about is that the noise everyone hears is more like a leak in the air intake system.

Hopefully S&B drops their full kit soon since I’m sure they won’t release something that negatively affects the vehicle.

I had an S&B on my 24 Cummins rebel and the sound difference was night and day.

I understand the RHO already comes with a CAI so I doubt there is really any improvement available. But hopefully the sound can be improved because these turbos are some of the quietest I’ve ever heard. And I’m a sucker for turbo spool boost noises.

 

[Dcchris311]

If an air filter swap or the intake tube swap (or a combo) created an actual turbo spool noise with 0 hp gain, I would do this in a heartbeat. But what I’m worried about is that the noise everyone hears is more like a leak in the air intake system.

Hopefully S&B drops their full kit soon since I’m sure they won’t release something that negatively affects the vehicle.

I had an S&B on my 24 Cummins rebel and the sound difference was night and day.

I understand the RHO already comes with a CAI so I doubt there is really any improvement available. But hopefully the sound can be improved because these turbos are some of the quietest I’ve ever heard. And I’m a sucker for turbo spool boost noises.

It's not just a filter and tube being swapped on my system. I removed the paragraphs that described my intake and why theres an increase in boost. The only details that were posted are about the filter.

 

[Dark Knight G45]

It's not just a filter and tube being swapped on my system. I removed the paragraphs that described my intake and why theres an increase in boost. The only details that were posted are about the filter.

I wasn’t responding to you. I was saying just in general. The design of our RHO intake looks identical to an aftermarket system except you have the benefit of a dedicated “ram air” forced air from the hood scoop sealing into the air filter/box.

Larger diameter intake and exhaust generally give some gains, especially on turbo cars. How much may be negligible.

But my post was that I literally just want a system that doesn’t lose power and is generally safe (for the warranty). I specifically want to hear the turbos.
On my Porsche and McLaren the gains and sound difference for an intake weren’t worth it. Exhausts made a huge difference tho.

On my Nissan GTR, mitsu Evo, and Cummins Ram, the intake allowed the full turbo spool noise.

Just rambling I guess…

 

[Faze]

Added it to Chatgpt as well and I like my answer better I just can't sleep well until I prove the aftermarket CAI is total waste of money for our trucks.

Also I remember that Chatgpt always tries to agree

Why a Cold Air Intake Doesn’t Add Much Power​

• Modern engines (like your RHO’s Hurricane) already have well-designed airboxes that pull cool air.
• A CAI might lower intake temps by 5–15 °F, but after the turbos and intercooler, that translates to only a tiny change in charge temp.
• Net result: maybe 1–3% more oxygen density, which is only a handful of horsepower. Most of what you “feel” is intake sound, not power.

---

🌬 Why a Freer Filter Doesn’t Raise Boost 2 psi​

• Turbos work on a pressure ratio. Less restriction at the filter means they can breathe a bit easier.
• Physics alone could raise boost 1–2 psi if the ECU didn’t step in.
• But on modern, torque-based ECUs, the MAP sensors and wastegates regulate boost. If pressure creeps up, the ECU just bleeds it off to hold the target.
• So you don’t get more boost — you just get slightly less turbo effort and a little cooler charge.

---

If You Did Gain +2 psi​

• That would mean about ~5% more air mass.
• If fueling and timing were adjusted to match, you’d see around 5% more power (≈ +20–25 hp on a 500 hp engine).
• But: you only get this with a tune that raises boost targets, not from a drop-in CAI or filter.

---

Bottom line:
A cold air intake and freer filter don’t raise boost or power much on their own, because the ECU regulates pressure. They make the turbos’ job easier and can support a tune, but the real gains come from ECU reprogramming, not just bolting on a CAI.

 

[Attakracer]

Well I bought one from our forum member here. Got the tube and better air filter. In my opinion it should allow the truck to breathe more. Usually more air means more power. Based on all the videos from people that have installed with tunes they are getting more power vs not having it.

I would guess the "more power" is coming from the tune !!! RHO already has CAI !!!

 

[Don50BMG]

I'll be doing some dragy pulls and datalogging this week.
Yeah, at first I didnt understand how I'd gain an additional 2psi so I went to ChatGPT it explained how it's possible. Im going to blank out certain words as im still developing the CAI. But it's essentially what @INTIMD8R said in his post.


ChatGPT:

That +2 psi gain is actually very plausible, and here’s why it happens with an intake like yours:


---

1. Reduced Restriction at the Filter

*Paragraph was removed*

Increased the effective filter area feeding the intake.

*Removed*

*Removed*


That efficiency lets the turbos pull air in with less effort, which directly translates into a higher manifold pressure.


---

2. Improved Compressor Efficiency

Turbos don’t “make” boost out of nothing; they compress what they can draw in. If the inlet is restrictive, the compressor works harder, generates more heat, and may hit flow limits sooner.
*Removed*

The compressor map point shifts slightly (more airflow at a given shaft speed).

The turbo doesn’t need to spin as high to hit a target boost → sometimes the ECU allows more headroom before wastegate duty caps it.

Result: observed boost rise.



---

3. Pressure Ratio vs. Flow Balance

Think of boost as resistance to airflow. By reducing restriction at the intake side, you’re improving the balance of the whole system (compressor → intercooler → intake manifold). The system can move more CFM for the same effort. That often shows up as a higher peak boost reading under load, even without a tune change.


---

4. Heat and Density Effects

Lower restriction → cooler intake temps before compression. Cooler air entering the turbo is denser, so when compressed to the same target pressure, it yields slightly more manifold pressure (and mass flow). That’s often seen as 1–2 psi more boost on the datalog.


---

In short: your intake isn’t artificially adding boost—it’s letting the turbos operate more efficiently, so the engine can achieve a slightly higher pressure and flow under the same control strategy.

Your answer is spot on, I have a cat6 installed and installing the AFE with red carbon fiber tube today.

 

[Dcchris311]

I would guess the "more power" is coming from the tune !!! RHO already has CAI !!!

It has a pretty restrictive filter from the factory. That filter’s really meant for deep filtration in off-road conditions, which you don’t need for daily city driving. A less restrictive filter would free up some airflow and give a small bump in power.

 

[Dcchris311]

Your answer is spot on, I have a cat6 installed and installing the AFE with red carbon fiber tube today.

Heck yeah!! Thanks for confirming! By the way, let me know how you’re liking that intake. Mine’s going to be nearly identical to their setup, and I’m honestly stoked that my design and implementation lined up so closely with AFE’s approach.

 

[Attakracer]

It has a pretty restrictive filter from the factory. That filter’s really meant for deep filtration in off-road conditions, which you don’t need for daily city driving. A less restrictive filter would free up some airflow and give a small bump in power.

I don't see how there's any gain when the computer controls everything ! And, IF you could "bypass " the computer, I can't see a filter (less restrictive) giving any more than like .1% gain. Which I don't think would be worth the risk of less filtration !!

 

[Dcchris311]

I don't see how there's any gain when the computer controls everything ! And, IF you could "bypass " the computer, I can't see a filter (less restrictive) giving any more than like .1% gain. Which I don't think would be worth the risk of less filtration !!

I’ll be doing some dyno pulls next week. I’ll start with a pull using the OEM intake, then follow it up with my intake setup and a less restrictive air filter.

When it comes to filtration, just because a filter is less restrictive doesn’t automatically mean it filters less. You can have a design with more pleats, which increases the overall surface area and allows more air to flow through without sacrificing much filtration efficiency.