I know that this issue has been brought up many times and the answer usually becomes 5.0 swap. While I would love to do this, I am unsure about the CARB angle in that the engine must be the same year or newer and the Explorer stopped getting the 5.0 in 2001 and I have a 2003 Edge edition 2wd 5spd 3.0 currently.
My question is, what could I do to get all the smog crap that I would need to make the swap work since I'd need to get the engine from another vehicle or crate? Would it be better to do internal modifications to my 3.0 or a 4.0 SOHC while ensuring that I could still pass smog?
I just want to be able to carry a modest load and play in the sand, nothing excessive.

 

Only way to make a 3.0l go faster is to put it in a lighter vehicle, i.e. go cart.
You can swap mechanical cooling fan for an e-fan, that frees up some power and you get better MPG, doesn't change emissions.
Any engine changes will effect emissions, computer tuners can increase available power and also have a "test mode" for passing emissions tests, no that is not like a "chip", lol, they don't really help.

Best bet would be to look for a 4.0l SOHC Ranger you like then buy it and sell the 3.0l Ranger.

Engine swaps in "smog testing" areas can run into some extra costs, if you are just swapping a 3.0l for another 3.0l then it is fairly straight forward.
When you change engine size(VIN number) then you need modified title change.
So after the swap is complete you have to pay a vehicle inspector to certify it as "road worthy" they will also test emissions.
If it doesn't pass inspection then you have to fix what was wrong and pay again to be retested.

So it isn't just passing smog test when changing engine size.

 

I have experience in performing engine swaps in other vehicles, I just don't know if I could perhaps harvest the smog and electrical components from a 2001 and get a 2003 crate/donor engine and it'll all match up. My 3.0 with 4.11 rear and 5spd already out accelerates the 4.0 so it's not a speed issue so much as a power POTENTIAL. With my current 3.0 I could potentially do a 3.3 stroker kit, but I am unsure if emissions will be increased too much (an integra 1.8L with piston and crank upgrade still passed smog...). So maybe I could do a 4.0L swap, get it ref'd, then build the bottom end. But is either build even worth it, or possible with emission concerns. This question is best suited for anyone who has actually built either motor from the bottom up or performed the 5.0 swap in a 2002 or newer ranger to offer advice from experience.

 

I think you could get better info for a build from local(Calif.) custom build shops, they do it daily and have to deal with Calif. emissions.

And I image more than a few 3.0l OHV engines have been stroked and camed and also meet emissions