2.0 SOHC swap to DOHC

Hello, I have a 1986 Mitsubishi mighty max 2WD 5 speed. I believe it's the base model because it doesn't have power steering or A/C. I am looking to get more power out of it and possibly a big build and I had originally wanted to find a 6 bolt eclipse engine for it, but I was talking to a guy the other day and he said I could just replace the head with a DOHC and it would be fine. I am wondering if this would be possible and easily achieved. Would it be cheaper to just swap the heads or buy a whole new engine? And what would the compression ratio of my engine be? I believe my engine is a G63B. It's the original engine in the truck. any help would be appreciated. Thank you.

If your going to go with the DOHC head, might as well slap the turbo in with it. I have the same year you have with a SOHC and made some changes for low end torque that I needed. There is quite a few things you can do to these motors and stay in a reasonable budget. Carb, header, cam, distributor curve, machine work to intake and head. Droppedmitsu has a great thread about replacing head to DOHC and adding turbo. My thread has some stuff on the SOHC improvements and there are many more thread builds here that can point you in any direction you like. You can find most in the Gen 1 / Gen 2 forum threads. Check your pricing for anything you plan to do for more horsepower. Parts for these trucks can be hard to find sometimes and can start to add up cash quickly. Dropping a V6 or V8 in compare to improving a 4 cylinder come very close to each other in cost. Parts for an American motor and trany can be found a little easier also and cost a hell of a lot less in most cases.