I've seen Jeep YJ's advertised on eBay with a V8 stuffed under the hood... Now I'm wondering if it is an easy swap and what major work needs to happen before the engine can go in. Let's assume that the Jeep doesn't have to pass any emissions tests afterwards...
Stuffing a V8 under the hood is fairly simple if you have fabrication skills. The problem lies in making it work. The cooling system needs upgrading. The stock transmission must be adapted or replaced. The rear axle will not survive long. The fuel system must be adapted. The gauges have to be hooked into the new sensors, and the starter & alternator must be adapted into the vehicles wiring harness. And if it's Fuel Injected, you need to wire a complete engine harness.
It's certainly do-able, and if you keep it carburated it's much simpler. Personally I'd love to get a complete powertrain from a 5.3 Chev, with their 5 speed automatics. It's a LOT of wiring but do a bit at a time and keep it simple, and you've got 315hp/338tq and better fuel mileage. Swap an 8.8 in the rear to match your upgraded D30 front and it's good to go.
Depending on which motor you go with will determine the amount of work involved. They will all require motor mounts, adapters and welding. I am running a 2008 5.3 with the 4l60e trans. It took three months to finish the swap and another month to work out some bugs.
Horsepower is like a hot girl with STDs. You know you want to hit it but you're afraid of the consequences.
I "was" in the process of dropping in my 5.7 TBI (currently torn down for rebuild) and 60e out of my '95 burb, but now I'm going to go with a lower mileage LQ4 or 9. More powerful AND better fuel economy, and ODB II to boot.
I gotta agree, need the fuel injection if you plan to do any off reading that includes ascents and decents. All told, TBI is probably the easiest fuel injection you can do. No high angle fuel starvation, no electronic issues.
After owning a Denali for a few years, I just want the 6L in there...