Power on the 2.5?


Here is a link to a page which gives some numbers for the 2.5 throttle body swap:

4.0L throttle body swap

If these figures are accurate, is seems that swapping out the throttle body is easily the biggest single improvement for the money, as bored out bodies are available on eBay right now for $90 plus a core charge. Other things, such as the electric fan conversion, air intake and exhaust modifications help too, but all cost much more, and their gains are smaller.

So, while a 4.0 still makes more total horsepower, given that the 2.5 engine weighs hundreds of pounds less than the 4.0, the difference in power to weight ratio looks to have just become quite a bit less.

you could also order a 62mm from BOUNTY HUNTER which has the taper removed if I am not mistaken.
 
Not to be a prick, but on the intake side, you want it to be as smooth as possible. The theory with those "Vortex Generators" is that the gas and air mix better. But in most cases, we are running MPFI, which means the injector throws the fuel in at the last second, meaning the only good those spacers do is restrict airflow. I would rather spend my money elsewhere.

Oh, and by the way, when you say keep up with the 4.0L, you mean on the trails or on the highway? I regeared to 4.10, installed themost aggressive mopar cam available, run PD Ignition with plugs gapped at .060, snorkel with Airhog high flow filter, high flow cat, borla cat back, efan, roller rockers, snorkel (CAI effect and ram effect), 19# injectors and 46PSI FPR, and although the 2.5L performes right up there with any 4.0L I have seen on the trails, it still struggles a bit on the open road at highway speeds; I think going to 5.13 gears would fix this, but that means 2 new axles, so it's staying like it is (it's not horrible bad, but it's no 4.0L).
 
You can only do the 4.0L throttle body swap on the MPFI 4 cyl. That didn't happen till '90 I think? Swapping TBI to MPFI, running bigger injectors and 4.0L throttlebody would perk it up. Would anyone be interested in a stroker 4? ;)
 

Re: Jeep Interior lining. Looking for a decent product?

I have an 88 2.5L 5speed YJ and im wondering if theres a way other thn a motor swap to get some more power on these? havent seen any air intake kits out? and not much else? Im going to run 35's, 6" of lift and 4.88's soon so i would like to figure out something if possible. But it is only a small distance commuter and a trail beast foir me. So anythig would be great thank you.

just do the swap :)
 
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