Swap?

[oregonphil]

I am not looking to do a swap myself, just curious. After a someone does a swap of some sort; LS, diesel or whatever, beside the pride and joy of having done the work, which I know is a big thing for all of us. I imagine HP may be better (LS) or torque (diesel) maybe even reliability. But what kind of improved MPG do they get, if any, in our FSJ concrete blocks? It would take years, if ever, to to see a return on the investment of your time and money vs. just rebuilding your engine to get a similar results.
Don't get me wrong, I am not being critical. Just wondering.
Actually, I think it's like I tell my wife when she asks "why would that guy jack up that Pinto"... 'cause he can.
Guess I had too much time on my hands this AM. Sorry if I wasted yours.

[Stuka]

In short, getting better fuel economy should never be the driving reason for an engine swap. Because as you state, it takes a LOT of miles to recoup that cost.

Power and reliability are the main drivers. And for some years, the inability to rebuild the factory engine due to lack of parts (AMC 327 guys for instance).

A diesel could increase fuel economy by quite a bit, but its also the most expensive swap.

[ProTouring442]

I went from a worn out, leaky, horrible mileage factory engine to a smooth, easy starting, no leaks, double the mileage and nearly double the horsepower engine that has done over 60,000 trouble free miles since the swap. That's why.

[tgreese]

Agree that you can't make a modern-equivalent vehicle from your Wagoneer. Too many inaccessible advances in the weight and efficiency of mechanical parts, and aerodynamics (including ride height).

Some of the Wagoneer's technology, sp. body shape, dates back to around 1961. That's 60 years - six decades. Modern engines are generally more durable than your original engine, and have lower emissions, better drivability (all weather turn-key starting, anyone?) and more durability. These are all significant advantages.

That said, based on fuel cost, I would guess maybe 1 in 50 such engine swaps eventually breaks even, much less ends up ahead. I would guess the various MPI SBCs and their drivetrain comes closest to breaking even eventually. Diesels can do better on fuel economy, though I kinda sorta think diesel swaps are too expensive overall to ever make back the "investment." Nobody is going to drive their hobby car a gazillion miles in the next three years ... people's lives just aren't stable enough to make this "investment" for the next 10 or 20 years, and there are ample better places to put your money.

Do it because you want to, because it's fun, because it's satisfying. Cars in general are a terrible (losing) investment.

[fulsizjeep]

I'm with Tim on this. Do it because you can and want to.

[ArchitectJS]

I stayed with my 258. As a noob car guy, i had a horrible time trying to get it run well. My engine was sound however, compression on every cylinder was very good and even across all cylinders. I added Holley Sniper and Hyperspark. Now i have an engine that starts immediately and accelerates perfectly. I can make 70 mph easily, which is plenty good for a truck that's just going to put around town. To me thats a win and no swap was necessary.

I'm sure it will blow up soon after paint and body is complete however.