Hello, I own a 1994 Jeep Wrangler with a 2.5L and automatic transmission. Since I have lifted it and put on the 33's I have noticed a loss of power. Wonder why? Any way my question is, what all would be involved in swapping in a 4.0L or will any of the Chrysler V8's swap in without a tranny swap. I have only dealt with GM's in the past and know what will interchange. A small block Chevrolet swap is not out of the question ,and I would be in a much more familar territory. Any help would be greatly appreciated.

Advance Adapters sells a kit to put a V8 Mopar in the Jeeps. Your stock tranny will not hold up though.
Even going to the 4.0 I dont think the tranny would work.

You will definitely need to swap the transmission when you do the engine. If you just go to the 4.0L, you can get away with your stock axles for a while, but if you go to a V8, both axles should be swapped out as well. When I was doing the research to do the same thing, it was just as easy to swap to a SBC as a 4.0L from the 2.5. I am not very familiar with the Mopar V8 swaps however...

Dude, all you have to do is replace your gears in the axles to 456's, and you will breath life back into your Jeep. A hell of a lot cheaper fix. I have seen 4 banger Jeeps with 44" tires on them, and they just re-gear..........no problem. Problem solved.

You may end up upgrading the entire drive train. A V8 is generally longer than a 4 cylinder so everything gets shifted back. You will probably have to replace the tranny, maybe even the transfer case, and the drive shafts will probably have to go as well. Should be a lot of fun. Its a great opportunity to bulletproof the underside with top notch equipment.

I would also recommend a Tera low conversion, so that you get a 4:1 ratio in your transfer case. The standard 2.73:1 flat sucks.

You move the engine forward of the stock location.
There is more than enough room to leave the transfer case in the stock location.
One of the hot setups on 2.5L YJs is to put a Klune V box in.
You shift the engine forward ~6". Still plenty of room.

The D30 will live up to a V8. Heck the early cj5 crowd run V8s with the D27 which is weaker than the D30.

It would be an easier swap to put a V6 in it. A Buick 231 or a GM 4.3 makes all the power you can want in a Jeep.
My cj5 has a V6 in it.
I will one day place a Mopar V8 mill in my YJ though.
But if it aint broke, dont fix it.
You would be way ahead of the game money wise to swap your gear ratio for 4.56s or 4.88s.

I've been looking at those 4.6l strokers lately, and they put out some serious numbers.

Yeah, the only thing that gears will do is control the rpms. The heavier tires will affect your power as well as greater wind resistance. I'm looking into this conversion myself. My findings point to a 350 with an NV4500. NP231 is more than capable of handling horsepower from this motor. All in all 8-10 grand seems pretty accurate as far as price to get everything done right.