Cold Air Intake Benefits?

[kd1yt]

The one and only different air filter option I would want to consider swapping out to is to be able to run a Donaldson blue nanofiber filter element - they flow air really well and also filter really well. Unfortunately they are not really available for light duty vehicles. For a few years Amsoil was selling the Donaldson media in 'EAA' air filters but that was for not very many years and well before the JL/JT platform, and, as far as I know, there isn't any prior Jeep (or other) make/model with the same size and spec filter element as the JT for which I could hope to find a new old stock 'EAA' that would properly fit the JT intake.

If I could get a Donaldson, I'd put it in the stock airbox - I really don't believe that the factory would have any reason to not very-highly-optimize this particular "stock" part of the vehicle for both HP and MPG and I don't want to get into remapping, I just don't have bandwidth. I do believe it's probably very possible to get improved performance if you get into extensive and meticulous re-do-s of intake, exhaust, and mapping, all in systematic ways, but again, no bandwidth here for that.

If one of the CAI options could run some version of the Donaldson filtration element, I'd consider that, if it's otherwise well-designed, but as far as I know, none of the CAIs for this platform use or are set up for a Donaldson element.

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[foo.c]

The one and only different air filter option I would want to consider swapping out to is to be able to run a Donaldson blue nanofiber filter element - they flow air really well and also filter really well. Unfortunately they are not really available for light duty vehicles. For a few years Amsoil was selling the Donaldson media in 'EAA' air filters but that was for not very many years and well before the JL/JT platform, and, as far as I know, there isn't any prior Jeep (or other) make/model with the same size and spec filter element as the JT for which I could hope to find a new old stock 'EAA' that would properly fit the JT intake.

If I could get a Donaldson, I'd put it in the stock airbox - I really don't believe that the factory would have any reason to not very-highly-optimize this particular "stock" part of the vehicle for both HP and MPG and I don't want to get into remapping, I just don't have bandwidth. I do believe it's probably very possible to get improved performance if you get into extensive and meticulous re-do-s of intake, exhaust, and mapping, all in systematic ways, but again, no bandwidth here for that.

If one of the CAI options could run some version of the Donaldson filtration element, I'd consider that, if it's otherwise well-designed, but as far as I know, none of the CAIs for this platform use or are set up for a Donaldson element.

Volant power core.

 

[be77solo]

Cold Air intakes on their own only let you hear the engine more.

Winner Winner Chicken Dinner! And boy do I LOVE the sound it makes

Welcome to the boards!!! Nice looking Willys!

 

[Jeepin' John]

Sorry, a little late to this discussion. (Just joined) I’m the Engineering Manager responsible for the Clean Side Duct from the AB to the TB. Long story short, unless you want a full blown novel, the stock system is optimized considering many items.

Cold Air intakes on their own only let you hear the engine more. In order to get the full performance benefits you have modify the mapping of the ECU.

My suggestion, just make sure you keep a fresh Wix filter in your box. The amount of testing we go through to optimize the entire system for that specific engine is pretty intense with years of development.

just so i'm understanding this correctly, the oem setup is designed as a "cold air intake", but when you say "cold air intakes on their own only let you hear the engine more" are you really referring to "aftermarket intakes"? (Since the oem intake is a "cold air intake")

also, did you work on the mopar intake tube as well, or just the oem? Curious as to any design background / info on the mopar tube since i bought one i'm getting great gas mileage with the mopar intake / borla exhaust on the factory tune. Currently 18.5 mpg city on 33's and 3.73's (sport s)

 

[ShadowsPapa]

just so i'm understanding this correctly, the oem setup is designed as a "cold air intake", but when you say "cold air intakes on their own only let you hear the engine more" are you really referring to "aftermarket intakes"? (Since the oem intake is a "cold air intake")

also, did you work on the mopar intake tube as well, or just the oem? Curious as to any design background / info on the mopar tube since i bought one i'm getting great gas mileage with the mopar intake / borla exhaust on the factory tune. Currently 18.5 mpg city on 33's and 3.73's (sport s)

I was hitting 20+ on stock engine, 33s and 3.73:1 gearing. That's combined mileage.
Trip to and from Fort Wayne a year ago saw 19-20 mpg on 33s.

I'm still doing 21 on 32.2" tires (33's are generally 32.8") tires. That's combined. I do 18-19 all city.

No offense, but if 18.5 is great - how bad was it before? And can you fully attribute the increase to the devices, or was it more engine loosening up and PCM learning?

Is the Overland not a heavier truck than the Sport? Maybe yours is a loaded Sport?

 

[DPF140]

Yes, I oversaw the design of the OEM "Clean Side Duct" is how we refer to it. From the Airbox to the Throttle. We designed and currently manufacture the 3.6L, 2.0L and the Diesel Clean side duct assemblies for the JL/JT. Actually I have a Patent on the Clip between the bellows and the Airbox on the Diesel.

When I say "Cold Air Intake" I'm refering to the aftermarket options (Mopar, K&N and such) which we don't work on. Those items allow your engine to "breath" better, however unless you change the programming of your ECU to dump more fuel to match the increased ability to breath, the stock ECU will automatically adjust mix of the A/F for the desired fuel efficiency ( think sea level / a mountain top). Yes, at the top of the mountain you may get better gas mileage than a stock... but it would be marginal. Mighty Car Mods on Youtube has a nice video on it... it's a few years old but gets the point across.

The "resonators" on the OEM duct is only meant to cancel the undesired "sounds" coming back out of the engine. Think of it as blowing air across a bottle and having different sized bottles to match the frequency of sound. Those resonators and 1/4wave tubes do not restrict air flow. That's why a straight duct "makes it sound better" your just no longer canceling the sounds.

 

[Jeepin' John]

I was hitting 20+ on stock engine, 33s and 3.73:1 gearing. That's combined mileage.
Trip to and from Fort Wayne a year ago saw 19-20 mpg on 33s.

I'm still doing 21 on 32.2" tires (33's are generally 32.8") tires. That's combined. I do 18-19 all city.

No offense, but if 18.5 is great - how bad was it before? And can you fully attribute the increase to the devices, or was it more engine loosening up and PCM learning?

Is the Overland not a heavier truck than the Sport? Maybe yours is a loaded Sport?

18.5 only "city" no highway at all - carpool, idling, morning rush hour, city traffic. I haven't made a highway trip in a while. My sport is "loaded" when i pick up the kids

before i was around advertised 17 city

 

[Jeepin' John]

Yes, I oversaw the design of the OEM "Clean Side Duct" is how we refer to it. From the Airbox to the Throttle. We designed and currently manufacture the 3.6L, 2.0L and the Diesel Clean side duct assemblies for the JL/JT. Actually I have a Patent on the Clip between the bellows and the Airbox on the Diesel.

When I say "Cold Air Intake" I'm refering to the aftermarket options (Mopar, K&N and such) which we don't work on. Those items allow your engine to "breath" better, however unless you change the programming of your ECU to dump more fuel to match the increased ability to breath, the stock ECU will automatically adjust mix of the A/F for the desired fuel efficiency ( think sea level / a mountain top). Yes, at the top of the mountain you may get better gas mileage than a stock... but it would be marginal. Mighty Car Mods on Youtube has a nice video on it... it's a few years old but gets the point across.

The "resonators" on the OEM duct is only meant to cancel the undesired "sounds" coming back out of the engine. Think of it as blowing air across a bottle and having different sized bottles to match the frequency of sound. Those resonators and 1/4wave tubes do not restrict air flow. That's why a straight duct "makes it sound better" your just no longer canceling the sounds.

gotcha, so at low rpm, if iat goes from 80 degrees to 110 degrees, all else being the same, you'll get the same gas mileage?

 

[DPF140]

somewhat... Air density/pressure in the mountains (altitude) is thinner/lower... so if your aftermarket intake is a larger diameter and the filter is more porous it may be able to make up for the drop in air pressure/density. The other point of a "Cold Air Intake" was to pull fresh/cold air from outside of the engine bay where it's obviously cooler... but OEM's are already pulling from fenders and grill's these days, so the benifit isn't much on our JL/JT's as it would be on say a TJ.

That all being said, I get the reason for them... I love the sound of an engine... intake and exhaust! In fact, I'm going to make my own OEM intake without the large welded on resonator so I get those low notes to pass through without the higher ones while still having it look like the OEM intake!

 

[Jeepin' John]

Thanks for the clarification. So cold air is better than hot air - it's just that the oem intake is already a cold air intake, so an "aftermarket" intake doesn't make as much of a difference

 

[ShadowsPapa]

Thanks for the clarification. So cold air is better than hot air - it's just that the oem intake is already a cold air intake, so an "aftermarket" intake doesn't make as much of a difference

Pretty much it - these are aimed where they are with baffles and guides to pull cooler air already. It's not going to get much cooler putting a hole in your hood because these pull air from away from the engine bay and engine area.
There's such a thing as too large a pipe going in and too large a pipe coming out. It's a system, end to end.

 

[IamWardicus]

I just got the Banks Dry Filter intake as I wanted a bit more sound. I got my money's worth... At WOT it's *Loud*. If I don't do that it's not noticeable at city cruising. I'll check out highway in the next day or two on a short run to the mall for lunch. Since I don't often carry a passenger it's not a deal breaker, however if you've a heavy foot and have others with you, you might want to look into another option.
I also contacted Livernois to ask if they update their tune at all for the slightly increased airflow potential of the intake. I'll post back once I hear from them & test a new tune if they can do anything else with it.

 

[ShadowsPapa]

So what we're saying with these "intakes" is that the factory setup is the same size as, or smaller, than the throttle body opening at WOT so it restricts beyond what will flow through the throttle when open wide.

 

[DPF140]

So what we're saying with these "intakes" is that the factory setup is the same size as, or smaller, than the throttle body opening at WOT so it restricts beyond what will flow through the throttle when open wide.

I don’t remember the exact diameters, but I can check tomorrow at work. If memory serves the AB outlet is close to 80mm. Our duct is an oval shape across the fan shroud for clearance (same equivalent diameter) then the 90 into the TB bellows has a very specific shape we optimize with CAE software to avoid negative pressure on the inside bend. If you just use a 90 elbow shape (like a PVC plumbing pipe) you will create reverse air flow on the inside corner. We call it a cobra head design to eliminate this issue.

That being said… intake noise from the aftermarket pipes is always great to hear! This is why I can’t grasp the whole pure EV crap. Whoppie, it’s quick off the line… after that… just another boring ride. I get hybrid… that makes sense.

 

[NateKY]

Other than at full throttle, your engine is throttled by the . . . the throttle. There is quite literally a plate blocking most of the intake manifold. This is how engine power is controlled.

So the only time the CAI even makes a difference in a most minuscule way is when you are at wide open throttle. (WOT). At WOT a CAI might allow a slightly higher manifold absolute pressure (MAP) which would allow a bit more power.

In all other circumstances, its absolutely irrelevant.

So tell me. When was the last time you were at redline at full throttle? Because that's the only use case where it makes a difference. And even then, maybe 1 or 2%.

Leaving every stop light and stop sign. Lol

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