[Cherokee_Chief]

Hey, y'all! Just got myself a 1987 Cherokee Chief, I-6 4.0, 4wd w/manual transmission. It needs some work. There's a crack in the exhaust manifold (a fairly common problem from what I've been reading), so I've decided to start there and am waiting for that and the front pipe, along with a new O2 sensor, to arrive.

 

[warriorsuspensions]

Welcome to the forum. And you are right, common problem

 

[Cherokee_Chief]

Welcome to the forum. And you are right, common problem

Thank you!

 

[andybrown006]

Hey Jeepers, I just bought a 2019 Cherokee Ltd 4x4. I love it. A grand Cherokee was my 1st suv. I have the 3.2L, 6 cylinder engine, and I want to beef it up. Does anyone know about cold air intakes? Do they do what they say they do? Will it hurt my engine?
glad to be here.
Andy

 

[warriorsuspensions]

I am not familiar with the new Cherokees. However the factory air intake is generally pretty good as far as cold air is concerned. If your intake is up by the grill area, as most are, you are already getting cold air. There may be some improvement in air flow from aftermarket set ups. But beware that many may violate smog laws if that is a problem. In CA where I live they have to be approved to pass

 

[andybrown006]

Ok, thanks. Is there a better way of getting more hp, torque & mpg?

 

[warriorsuspensions]

Good question. I am not familiar with the 3.2L. But it all boils down to more air and fuel in the chamber. Do some research on camshafts. If available go for higher lift and not too much more duration. These fuel injected motors don't do well with valve lift overlap. Not like the good old days with carburetors. And a good exhaust system is a plus too

 

[andybrown006]

Thanks. I did think about headers. Is putting on headers,& changing nothing else work ok?

 

[warriorsuspensions]

Non of that hurts. Tube headers will never hurt. Free flowing exhaust either. But the long tube headers which look totally cool are designed for camshafts with overlapping valve openings. The way they work is that when the exhaust valve opens the gases go through the tubes with sufficient velocity to create a small amount of momentum and draw a vacuum on the combustion chamber. If the intake is still open a little the vacuum is pulled on the intake too and draws more fuel/air into the combustion chamber.

That being said, headers don't hurt. But I don't think you will get the gains you are hoping for. Something that will work is a hydrogen cell, which is just seperating water into hydrogen and oxygen and routing down the intake. You can make your own, or you can buy kits. Either way, that is the most promising. I am working on my own that will be fairly sophisticated but you can use a simple one in a mason jar with an on/off switch for good results and increased milage. Lots of stuff on YouTube about them

 

[andybrown006]

Hydrogen cell? Huh. I’ll look into that
Thanks

 

[andybrown006]

Does Mopar make a cold air intake system, or a high performance intake manifold?

 

[warriorsuspensions]

That I don't know. But I doubt it

 

[Gluckmysock]

You can start at mopar.com.