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-   -   Cold air intake (http://www.wranglerforum.com/f282/cold-air-intake-153432.html)

vamil93 04-14-2012 12:54 AM

Cold air intake
 
Should I get one to double horsepower and get 50 mpg?

Just kidding. When I bought the LJ, it had an intake already installed by the PO. I saw a stock air box off of ebay for $7 and couldn't pass it up. Is there an advantage to putting it on and scrapping the intake? I know the CAI is doing little if anything for me now, will the stock box be an upgrade? I do a little light offroading, mostly DD to work and around town. Thanks in advance.

Mortalis5509 04-14-2012 02:21 AM

Yeah it will allow less crap into the engine and then you can sell that "CAI" to some mall crawler along with putting some money in your pocket.

lee indy 04-14-2012 02:27 AM

+1 some tard will buy yours for more than 7 bucks. hell sell it here there are thousands of people that believe that marketing crap

56cj5 04-14-2012 02:38 AM

I do actually find performace and drivability gains with my 2.4L. With a CIA. But it's not a jeep engine it's a neon engine. I'm sure that makes a huge difference . But it's just my opinion ....

lee indy 04-14-2012 03:01 AM

all an intake does is give you a noise sucking noise when you accelerate and lean out your engine. unless you retune for it all your doing is hurting your engine.

Black98 04-14-2012 03:04 AM

If you got a 4.0L and its your DD keep it on (depending on brand). I gained a solid 1MPG peak with my cold air and 63mm TB. When my right foot isn't having fun my peak MPG on the tank went from 19.2 to 20.4. I have calculated my MPG every tank since I got it and had a good solid 2 years of high 18s and low 19s. The 3 fillups after my CAI were all above 19.2MPG but I didn't hit 20 till later. If you get the CAI for free, like you did, you get that savings boost without paying a cent.

lee indy 04-14-2012 03:22 AM

really throttle body spacer? on an injected engine? like i said some one will buy that thing put the factory on and get a good filter.

and throttle body spacers dont do anything for a injected engine. look it up if you dont believe me.

Mortalis5509 04-14-2012 04:02 AM

Quote:

Originally Posted by Black98
If you got a 4.0L and its your DD keep it on (depending on brand). I gained a solid 1MPG peak with my cold air and 63mm TB. When my right foot isn't having fun my peak MPG on the tank went from 19.2 to 20.4. I have calculated my MPG every tank since I got it and had a good solid 2 years of high 18s and low 19s. The 3 fillups after my CAI were all above 19.2MPG but I didn't hit 20 till later. If you get the CAI for free, like you did, you get that savings boost without paying a cent.

So how long is it going to take to pay off that intake?

lee indy 04-14-2012 04:13 AM

assuming you get peak all the time. 2 years to break even. and that doesnt include the extra maintenance problems it will cause. plugs for example. but dont take my word for it. i only do beta testing for a leading performance tuner company.

jgorm 04-14-2012 09:43 AM

Quote:

Originally Posted by lee indy (Post 2256848)
i only do beta testing for a leading performance tuner company.

who?

rrich 04-14-2012 09:44 AM

He He - This is the ONLY forum that perpetuates the rumors that the stock airbox/silencer is better than less restrictive types.
And they don't know how to seal the air inlets, so of course dirt gets in. They quote scam advertising comparison charts to prove their point.

And the misguided here also think Fram, Autolite and Bosch are the best brands.

And of course, they think Autozone sells quality parts.

Check out other Forums where people don't have their heads in the sand.

Mortalis5509 04-14-2012 10:27 AM

Quote:

Originally Posted by rrich
He He - This is the ONLY forum that perpetuates the rumors that the stock airbox/silencer is better than less restrictive types.
And they don't know how to seal the air inlets, so of course dirt gets in. They quote scam advertising comparison charts to prove their point.

And the misguided here also think Fram, Autolite and Bosch are the best brands.

And of course, they think Autozone sells quality parts.

Check out other Forums where people don't have their heads in the sand.

This is not the only forum that thinks stock is better.

rrich 04-14-2012 11:45 AM

Use your head here -
On the stock airbox muffler ALL the air has to go through that tiny little airhorn. It comes off, hold it over your mouth and go jogging with it. Try to breathe though it without choking for air.

The 4.0 needs LOTS MORE AIR than you do!

Now why do you think it'll work on your engine, but can't for you?

The stock airbox is designed to house the filter (and it doesn't even seal around it very well) , but it's main purpose is to silence the incoming air. Notice without it it's noisy. There are new car Fed Noise Laws they have to comply with - else why don't they put less restrictive exhausts on it?

THINK - use your head for more than just a rattle!

Jerry Bransford 04-14-2012 11:51 AM

There are only a few who still persist in believing the TJ's OE air intake is restrictive. Too bad they are so stubborn in believing that long-disproven myth.

As has been mentioned many times, Jeep specifically designed the TJ's air intake to be non-restrictive. And that is right from Jim Repp, one of Jeep's most senior engineers who started with Jeep back in the CJ days.

And I'm not going to get into a pissing contest with the few who still believe that myth so my lack of response to their retorts in this thread is simply that I won't waste my energy responding to their anguished cries that it is restrictive. :)

rrich 04-14-2012 01:59 PM

Of course Jerry should know, he's tried breathing through the tiny airhorn himself.
He's also faithful to Fram and Autolite!

The engineer - what would happen to his job and retirement if he was telling the truth? What would happen to YOU if you told people your employer was lying?

Yes, many of the claims by the aftermarket mfgrs is hype, but Jeep lies too. Why do they advertise it's an off road vehicle, then deny warranty claims saying it's been taken off road?

THINK!

Remus_Redbone 04-14-2012 03:09 PM

Quote:

Originally Posted by rrich (Post 2257881)
Of course Jerry should know, he's tried breathing through the tiny airhorn himself.
He's also faithful to Fram and Autolite!

The engineer - what would happen to his job and retirement if he was telling the truth? What would happen to YOU if you told people your employer was lying?

Yes, many of the claims by the aftermarket mfgrs is hype, but Jeep lies too. Why do they advertise it's an off road vehicle, then deny warranty claims saying it's been taken off road?

THINK!


Think; it is a good suggestion. How many jeeps does Chrysler sell? What is the purpose of the stock air filter? How many more would they sell if they could put a larger fuel mileage number on the window sticker? How many fewer would they sell if their engines all started using excessive amounts of oil at 75k miles? There's a relatively large number of engineers running fairly advanced tests on engine performance and longevity. They come up with what they believe is best for performance and longevity and future sales. You can cut a hole in the hood and run a straight intake tube with no filter to improve performance and fuel economy.....for a while. You can run an oil-bath hepa-filter and get long engine life, but you'll have to buy a little more fuel. I like the compromise the engineers settled on.......

lee indy 04-14-2012 05:59 PM

Quote:

Originally Posted by Jerry Bransford (Post 2257629)
There are only a few who still persist in believing the TJ's OE air intake is restrictive. Too bad they are so stubborn in believing that long-disproven myth.

As has been mentioned many times, Jeep specifically designed the TJ's air intake to be non-restrictive. And that is right from Jim Repp, one of Jeep's most senior engineers who started with Jeep back in the CJ days.

And I'm not going to get into a pissing contest with the few who still believe that myth so my lack of response to their retorts in this thread is simply that I won't waste my energy responding to their anguished cries that it is restrictive. :)

im with you jerry. im done arguing with fence posts.

WaterDR 04-14-2012 06:26 PM

I am with you. Anyone that insists on wasting a single dollar on one of these things on their TJ should just dump their money in the garbage.

I am through trying to help people with this issue.

jgorm 04-14-2012 08:35 PM

I've said this multiple times. Underhood filters are dumb and you should never buy one, and if the stock intake sucks hot under hood air, you should look into other options. The only option for a CAI on a jeep is a cowl intake, or snorkel intake. (i think a snorkel is a total waste unless you waterproofed the entire engine, dash, airbag module, etc). With slow moving hot desert temps a cowl intake could easily be worth 20-30+hp because you would see <115F IATs vs >170F. Under normal temps you won't see much gain.

Mortalis5509 04-15-2012 12:53 AM

Why don't you do some research and then get back with us.

rrich 04-15-2012 06:32 AM

Try something - if you dare!

Use a remote thermometer - put it where a CAI filter would get it's air.
Put another one on the front bumper.
Actually see the temps at idle and at speed - that compares underhood temp vs ambient.

When I tried it, the difference at idle was about 10-15 degrees. At speed the difference was only maybe 2 degrees, if that.

Now consider at idle - do you really need extra horsepower? How much HP does it take to idle?

At a slow crawl? Obviously if you were to open the throttle up to use that "extra" - it would no longer be a slow crawl, would it?

At speed and under load is when you are able to use the extra HP, where it could make a difference, -- but how much more HP will you get with only 2 degrees difference?

But - the real purpose is to eliminate all the restriction from the silencer. A long snorkel tube is probably as restricting as the stock airbbox. But isn't the purpose of a snorkel for water crossings? Most are for mall looks and to impress little kids. Notice vehicles actually used for deep water also have a snorkel on the exhaust. The engine has to breathe out as well as in - so do we!

Some race cars use a hood scoop or some type of cowl induction - not really for the temperature, but properly positioned they are able to slightly get more air from locating it where the air pressure is higher AT SPEED. They can point it forward close to the front of the hood, or backward if close to the windshield, seeking the higher pressure areas.

But, in most cases with a carb it's detrimental - the higher pressure air causes it to go too lean at speed. If the carb was recalibrated to keep it rich enough to compensate, it's too rich at lower vehicle speeds when there's not as much pressure. Before going fast it has to get up to speed. It's a double edged sword.

The difference is only slight anyway, but when a few hundredths of a second can put you "in" or "out" of the money it could be important.
How much more money will you make if you can find a few more ponies?

Think - a 4.0 at 2500 RPM tries to pull in 5000 Liters a minute (2 liters each revolution times 2500, or 83.3 Liters a second,) far more than you can handle in your lungs. But you cannot breathe enough through that tiny air horn when exercising. What makes you think the engine can?

Chrysler/Jeep had to sacrifice some HP to comply with Federal noise regulations.

But, believe and do what you want, it's your Jeep!

jgorm 04-15-2012 08:14 AM

Quote:

Originally Posted by Mortalis5509 (Post 2259933)
Why don't you do some research and then get back with us.

Me? I've done more actual research and data collection on this than everyone on this forum put together.
Quote:

Originally Posted by rrich (Post 2260221)
When I tried it, the difference at idle was about 10-15 degrees. At speed the difference was only maybe 2 degrees, if that.

Now consider at idle - do you really need extra horsepower? How much HP does it take to idle?

At a slow crawl? Obviously if you were to open the throttle up to use that "extra" - it would no longer be a slow crawl, would it?

At speed and under load is when you are able to use the extra HP, where it could make a difference, -- but how much more HP will you get with only 2 degrees difference?

But - the real purpose is to eliminate all the restriction from the silencer. A long snorkel tube is probably as restricting as the stock airbbox. But isn't the purpose of a snorkel for water crossings? Most are for mall looks and to impress little kids. Notice vehicles actually used for deep water also have a snorkel on the exhaust. The engine has to breathe out as well as in - so do we!

Some race cars use a hood scoop or some type of cowl induction - not really for the temperature, but properly positioned they are able to slightly get more air from locating it where the air pressure is higher AT SPEED. They can point it forward close to the front of the hood, or backward if close to the windshield, seeking the higher pressure areas.

But, in most cases with a carb it's detrimental - the higher pressure air causes it to go too lean at speed. If the carb was recalibrated to keep it rich enough to compensate, it's too rich at lower vehicle speeds when there's not as much pressure. Before going fast it has to get up to speed. It's a double edged sword.

The difference is only slight anyway, but when a few hundredths of a second can put you "in" or "out" of the money it could be important.
How much more money will you make if you can find a few more ponies?

Think - a 4.0 at 2500 RPM tries to pull in 5000 Liters a minute (2 liters each revolution times 2500, or 83.3 Liters a second,) far more than you can handle in your lungs. But you cannot breathe enough through that tiny air horn when exercising. What makes you think the engine can?

Chrysler/Jeep had to sacrifice some HP to comply with Federal noise regulations.

But, believe and do what you want, it's your Jeep!

The horn was worth an average of 1hp.:banghead:
bone stock, 5 pulls
http://www.tricktuners.com/Uploads/2...to_5_stock.jpg

Removed the horn and did some more pulls. Looks to me that the horn is not a restriction at all.

http://www.tricktuners.com/Uploads/2..._8_no_horn.jpg

If you are only seeing 10-15F difference then you are well outside the norm, or tested it when it wasn't heat soaked. Unlimited04LJ has some real data from the stock IAT suggesting much higher differences. You don't need the hp at idle, but when you come up to a sand hill, or mud pit and need to hammer it, then you will be glad you have fresh cold air. The temps come down at speed, but my actual experience is that it takes about 0.5+mi at 50+mph to drop from 175 to 135. The acceleration was so bad I thought the jeep was broken.

UnlimitedLJ04 04-15-2012 09:35 AM

Quote:

Originally Posted by Black98 (Post 2256798)
I gained a solid 1MPG peak with my cold air and 63mm TB. When my right foot isn't having fun my peak MPG on the tank went from 19.2 to 20.4.

I had a CAI, and the engine idled like crap because the filter kept getting clogged with junk, and letting boat loads of dust into the throttle body. My mom has an 06 LJ, and she's gotten 21-22mpg highway before...no CAI, just bone stock with regular maintenance and stock 30x9.50R15 tires....but she drives like an old lady.

I have 4.88s/33s and can get 18mpg with the stock intake, if I really try...but I like skinny pedal too much to do that everyday.

Quote:

Originally Posted by rrich (Post 2257617)
Use your head here -
On the stock airbox muffler ALL the air has to go through that tiny little airhorn.

I've actually found the stock horn doesn't effect much, except IAT's (intake air temperature sensor).

Quote:

Originally Posted by rrich (Post 2257617)
THINK - use your head for more than just a rattle!

I've used my head quite a bit, and tried a bunch of different combinations myself. I've found the stock intake to actually be the best option unless you cut holes in your cowl or pipe the air intake outside the engine compartment in some other manner.

Quote:

Originally Posted by jgorm (Post 2258955)
With slow moving hot desert temps a cowl intake could easily be worth 20-30+hp because you would see <115F IATs vs >170F. Under normal temps you won't see much gain.

just to be clear so others understand what you're saying - the 20-30+hp isn't gained, just restored, with lower intake temps. The PCM automatically retards timing and adjusts A/F ratio as IAT (intake air temperature sensor) values increase, which lowers the power. I've also found above ~170-180F IAT's, the engine really looses power (noticable when highway driving).

Quote:

Originally Posted by jgorm (Post 2260385)
Unlimited04LJ has some real data from the stock IAT suggesting much higher differences. You don't need the hp at idle, but when you come up to a sand hill, or mud pit and need to hammer it, then you will be glad you have fresh cold air. The temps come down at speed, but my actual experience is that it takes about 0.5+mi at 50+mph to drop from 175 to 135. The acceleration was so bad I thought the jeep was broken.

I could care less about my IAT off-road, as long as it stays below engine temp....but on the road, I've found consistently lower IAT's, and quicker IAT drops when switching from street to highway, with a Windstar fender horn shoved in place of the stock horn...it draws air directly from behind the headlight. This was even better than just removing the stock horn entirely.

http://i133.photobucket.com/albums/q...e/DSC01981.jpg

If you're going to keep the intake in the engine compartment, then the good filtration of the stock box & lower IAT's offered by sticking the intake feed directly behind the headlight is about as good as its going to get, especially considering bang for your buck.

lee indy 04-15-2012 08:02 PM

Lets not forget the engine damage from.running to lean. Very few vielchels benefit from a new intake and none benifit without tunning. Do you really think you are smarter than the designer?

jeepwayoflife 04-15-2012 08:28 PM

Interesting about running too Lean... Will a CAI really do damage by forcing the jeep to run too lean? As far as bad filtration, I have a layer of 1ply papertowel over my CAI filter to help with the fine dust. Idk how much it helps but every few weeks I change it and its nice and brown. Seems to make no difference with blocking air or anything

EliasFaust 04-15-2012 08:31 PM

hell sell it here there are thousands of people that believe
http://www.australialuxe.info/013-1.jpg

Jerry Bransford 04-15-2012 08:53 PM

A CAI won't cause an engine to run too lean since a CAI can't force more air into the engine than the engine is requesting/pumping into itself.

Patrick H 04-15-2012 09:11 PM

Even if it did make it lean (it won't) you'd get a DTC/MIL long before it was too lean to do any damage.

jgorm 04-15-2012 09:34 PM

Quote:

Originally Posted by lee indy (Post 2262651)
Lets not forget the engine damage from.running to lean. Very few vielchels benefit from a new intake and none benifit without tunning. Do you really think you are smarter than the designer?

No Jeeps are map based so it doesn't matter.

Quote:

Originally Posted by Patrick H (Post 2263011)
Even if it did make it lean (it won't) you'd get a DTC/MIL long before it was too lean to do any damage.

Not true.

Patrick H 04-15-2012 10:38 PM

Quote:

Originally Posted by jgorm (Post 2263177)
No Jeeps are map based so it doesn't matter.



Not true.

It is true. How long have you been doing driveability diagnostics for a living?
EFI dyno tuner for Chrysler huh.


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