The Duratec 2.3L is used in the Ranger, is DOHC, and has a ton of go-fast parts for it from Cosworth. Its pretty pricey compared to a 5.0L build, but apparently 250 HP is fairly easy to get.
Then there's always the MazdaSpeed 2.3 Turbo engine...[/QUOTE]
I love Mazda, but they never really made a high HP rearwheel drive engine. (Other then the rotory), I think outside the box but I was never fond of the magic triangle engine LOL
The SR20 DET has 220hp and a huge aftermarket support. It is old school too, no drive-by-wire ect. You can get all the wirring diagrams off the net, because they have been swapped into nearly everything.
(have not seen a Mustang II SR20 yet)
It would be nice to put a Ford in a Ford, but Ford has not made a high HP 4Cyl RWD since the Turbo coupe.....which would make a great swap, but they are getting hard to find and there getting old. (No 25000km ones for $1890.00 with transmission)