We all know the story. “How do I make my 4 angry squirrels more angry?”. One thing that pops up a lot is the 4.0 TB on a 2.5. You can bore out the TB, get a spacer and bore that out, bore out the intake, and according to someone from the Quadratec forums said you can get an additional 16 HP from it!

Well, I have no idea if it’s true. I’ve seen lots of people say it works, that it doesn’t work, that it kinda works, and so on. However, it seems that this person also dyno’d it and it’s proven, but the post doesn’t have any images anymore. And I found it on a Wrangler forum.

https://www.wranglerforum.com/threads/4-0-throttle-body-on-a-2-5.1957/

My question is, is this worth it? I’ve seen some pretty compelling stuff about this “mod” that I want to do it myself, but i’m not sure if it’s actually what it says it is

So if someone could give some input into whether or not this would actually work, because if it does actually work and it makes a noticeable difference, then you bet my *** i’m going to do it.

 

Your 2.5 is not really gonna get any gain outta this without other modifications.
Sure you can do it, but you have told us that this is your daily driver. Your Jeep would be down for a while, as you have to take off your intake and exhaust manifold, then gasket match the opening on your intake.
So basically you are looking at two to three days without your DD.
Not to mention it ALWAYS takes longer, as once you start a project like this, you will find other problems.

There are plenty of videos on Screwtube about doing this.
And once again here is a link to Jedi: https://jedi.com/obiwan/jeep/2.5Lpower.html

I have been EGGXACTILLY where you are at with wanting some more ummmph! from my 2.5L . I feel your pain, really I do.
The lil 2.5 is a great little engine, but it is not new technology, so we are constrained at what we can do to it. If you have the money and time look to doing the stroker engine. But once you go down the road of modifications, be prepared to have to spend more money, and time on the project.
Good luck in your quest for MORE POWER!!!!

 

I say I want to mod out my 2.5 for some more power, but truth be told, I don’t have the time or the money. I want to put in a somewhat aggressive cam with some longer duration rockers, and some other things along the way, but truth be told, I don’t have any time to do it. She’s got 289k and has only had a top end rebuild, so i’m pretty sure one of my bearings is about to go. If that happens, I’ve found a short block stroker that just needs all the covers, and i’ll put that little stroker in and mount an AX15 to it.

Still, I love my 4 banger. I don’t care what anyone says, it gets better gas mileage. Sure, it might only be 2MPG better than a 4.0 2wd 5-speed, but when I drive 100+ miles a day, that 2 extra MPG really helps. Plus, it has some amazing torque for how small and slow it is. Might not be a lot of torque, but it’s more than what you would expect from a 4 cylinder