2.5L DIY cold air intake

[Tanker_01]

I am wanting to replace my factory airbox and the janky flex tube it uses for the intake. I have looked around at model specific kits but I figure with how simple it is it would not be difficult to just buy a generic one to the right diameter. Does anyone know what the diameter of the intake hose on the 1989 2.5L is? Has anyone done this themselves before? There arent any sensors that will be affected are there?

I will use this thread as a build/informational thread if I do go the route of making my own intake.

 

[Chris]

While I haven't done this, I should make you aware that a cold air intake will yield no power gains whatsoever on these Wranglers. Unfortunately that's not an opinion, it's fact.

The Jeep engineers themselves have mentioned on the boards back in the day. Some engines can indeed benefit from increased airflow, unfortunately these engines are not that lucky.

The other issue at hand is that there have been numerous tests performed, and all of the aftermarket air filters out there are not as good as an OEM style filter in filtering out the bad stuff from getting in your engine. That being said, if you go off-road any at all, a cold air intake will actually be doing your engine more harm than good.

If this were a LS3, LS7, or something along those lines, you could slap on an air intake and a tune and make some more power. Such is not the case with the Jeep Wrangler though

Not trying to be argumentative, just trying to help out

 

[Tanker_01]

While I haven't done this, I should make you aware that a cold air intake will yield no power gains whatsoever on these Wranglers. Unfortunately that's not an opinion, it's fact.

The Jeep engineers themselves have mentioned on the boards back in the day. Some engines can indeed benefit from increased airflow, unfortunately these engines are not that lucky.

The other issue at hand is that there have been numerous tests performed, and all of the aftermarket air filters out there are not as good as an OEM style filter in filtering out the bad stuff from getting in your engine. That being said, if you go off-road any at all, a cold air intake will actually be doing your engine more harm than good.

If this were a LS3, LS7, or something along those lines, you could slap on an air intake and a tune and make some more power. Such is not the case with the Jeep Wrangler though

Not trying to be argumentative, just trying to help out

No I fully understand and agree. I'm just wanting to do it because the stock airbox doesn't fit well in my engine bay with the aftermarket inner fenders.

 

[Chris]

No I fully understand and agree. I'm just wanting to do it because the stock airbox doesn't fit well in my engine bay with the aftermarket inner fenders.

In that case, I totally get it

Clearly you've done your homework. You just never know. A lot of guys assume you gain all this power, and are sorely disappointed when they find out they gained nothing other than some loud sound

 

[Tanker_01]

In that case, I totally get it

Clearly you've done your homework. You just never know. A lot of guys assume you gain all this power, and are sorely disappointed when they find out they gained nothing other than some loud sound

Oh yes 10 years of working on cars, 6 years of being a military mechanic and 4 years of mechanical engineering in college has given me enough wisdom to understand the pointlessness of cold air intakes. I too roll my eyes every time a 16 year old goes and spends $200 on a pvc tube and come filter and expect to get 20hp... I just have to do it on my Jeep because there's no room in the engine bay lol. I could figure it out myself obviously but I figured I would come here and ask if anyone has done it already and could share some insight before I went ahead and did it.

 

[Chris]

Oh yes 10 years of working on cars, 6 years of being a military mechanic and 4 years of mechanical engineering in college has given me enough wisdom to understand the pointlessness of cold air intakes. I too roll my eyes every time a 16 year old goes and spends $200 on a pvc tube and come filter and expect to get 20hp... I just have to do it on my Jeep because there's no room in the engine bay lol. I could figure it out myself obviously but I figured I would come here and ask if anyone has done it already and could share some insight before I went ahead and did it.

Someone always wants to argue with me every time I bring up the CAI thing. They'll say, "Well I've heard you can get 3hp or so.", to which I always reply that you can gain or lose 3hp just on back-to-back dyno runs depending on heat soak, altitude, temperatures, air conditions, etc. 3hp is not an actual measurable gain, that's just variances in all the conditions.

And then of course there is the whole idea that adding more air adds more power. YES, it can, but you need to open up the entire pathway, not just the intake. By opening up the intake, you then make the next bottleneck the intake manifold and cylinder head. So unless you plan on installing a larger intake plenum, porting the cylinder heads, and tuning the ECM to accommodate for this, you're wasting your time.

Of course it doesn't help that these companies make air intakes and sell them under bullshit marketing claims. I guess we were all young and dumb once.

Well, hopefully someone chimes in. Maybe @Fouledplugs knows a thing or tow. His YJs are far from stock

 

[Fouledplugs]

Seems like OP just needs something that fits his inner fender mods.

@Tanker_01 have you tried to look into fitting a YJ 4.0L air box, a TJ 4.0L air box, a TJ 2.5L air box, or even a TJ 2.4L air box? Surely one of those OEM kits could be made to fit in your engine compartment.

 

[Tanker_01]

Seems like OP just needs something that fits his inner fender mods.

@Tanker_01 have you tried to look into fitting a YJ 4.0L air box, a TJ 4.0L air box, a TJ 2.5L air box, or even a TJ 2.4L air box? Surely one of those OEM kits could be made to fit in your engine compartment.

Are those smaller or something? Is the throttle body diameter the same still for the 4.0? That would be awesome to be able to use something that still looks OE