Use the M5OD trans behind your 2.9L. It will bolt right up to a 4.0L. Its a good transmission, too. There are plenty of 4.0L rangers that have been totalled to the point where you could grab the drivetrain, electrical, and more for cheap. I have no first hand experience in turbocharging a 2.9L, but I do know a lot about the V8 Swap. How much would you be willing to spend? A 4.0L could be had and done for under $1000 with some time and research.
I've done the V8 swap. If you do choose that route, then be warned that there HAS to be a serious budget and a lot of research. There will be considerable downtime, also. If you go out and purchase a cheap car and switch everything over, you will be dissapointed. Most cheap cars ford built in the 80s and early 90s were less than 200hp (which is what you want out of your 2.9L). Say you pick up a 302 and C4 transmission. This combo would be the cheapest to run. Start with a seasoned block, inspect for trueness, no cracks, stress... You can get away with using the stock crank and connecting rods if you don't plan on major power or RPM. Keith Black makes some great entry level hypereutectic pistons for under $300. Take it to a machine shop, have them punch it 30 thousanths over and install new cam bearings, hot tank, blueprint, and the rest of the works. There's little use for the crappy E6 and E7 heads, so look for a used set of GT40 heads from a cobra mustang or Gen 1 Lightning (I've seen them for under $300). Do a nice street port and polish, then have a machine shop cut a 3 angle valve job. Find yourself a decent street cam to match the mild engine combo. Something from 1500-5500rpm should be enough. Go carbureted, since it is cheaper and easier. A nice edelbrock performer manifold will work smoothly with the cam and heads. Go with a nice reliable ignition system. Then, a 570-600cfm will be plenty to feed a 302 at 5500rpm. I would bet an easy 250rwhp from this combination (which is about double what your engine is throwing at the ground). A C4 is as common as a bic lighter, so use that. Find yourself an 8.8" rear out of a 4.0L ranger. This will be the cheapest and easiest to swap. I recommend long tube headers, but for budget shorties woud be okay. Find them for under $150. You will also need a radiator. A HD 4.0L will be fine for a mild 302, otherwise there are V8 rads. Honestly, I would say I have $8000 in my V8 ranger, but I also have an AOD 4speed auto with lentech's bells and whistles along with a pricey TCI torque converter. I think you could shave $1000 off if you went with a rebuilt C4.
Now, a 4.0L will be cheaper and easier. Look at the engine bay of the 4.0L donor vehicle. Take pictures, so you know where everything is located. Since you have a 2.9L already, the 4.0 will bolt into the chassis with 4.0L motor mounts. Use the 4.0s accessories and exhaust manifolds. Harvest the WHOLE harness from the donor vehicle. This will be a little tricky but with a haynes or chilton manual from both your truck and the donor vehicle, this shouldn't be too much work. The fun with a 4.0L is that you have the options of "go fast" parts where as their isn't a whole lot for the 2.9L. The 4.0L won't have as much power as a mild V8, but the price and difficulty will make for a better, easier, and more enjoyable swap.
You will learn a great deal from this. Then, a couple years down the road when you've had enough of the 4.0L and the truck isn't your daily driver anymore, go ahead and use the learning experience to drop in a 302. Hell, you get bored of that a couple years later and turn it to a high revving 331ci. Maybe you want a supercharged 351... the list goes on. We all dream, but you have to start somewhere. I built my first 302 when I was 14 with my father helping me via advice and plenty of books. Got it all together and it has low oil pressure. Well, it sounded great for the 15 seconds of break in before we tear it apart again only to find that I forgot the gasket that sits between the block and the oil pump.
Honestly bud, you have plenty of posts ranging from transmission trouble to extremes like turbocharging and V8 swaps. Start of easy and learn. There will be no fun in an engine swap if you don't know what you're up against. Not trying to argue with you, but you shot down the 4.0L idea. You show little knowledge of turbochargers and how they work (which is essential to doing a swap like that). You argue with the V8 swap because it will cost too much. Which leaves you with one more option, purchas a new vehicle with the powertrain you want. But, you won't do that because of sentimental value. To make it easier for you, I will just answer your question. Quick power from a 2.9??? Nitrous! Lots and lots of Nitrous. Make sure the race counts, because the 2.9L will only make it through a couple shots. (that is, at 200hp)
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All depends on how you look at it.
Also I cut off the entire original exhaust from the collector back and put on 2-1/2 inch exhaust with a cherry bomb, and it added more power and sounds pretty good once it got "broken in" also things like fuel injector cleaner help to on these older 2.9's, as i have found out. So yea just food for thought
