So last month my car was having over-heating problems and my father (a mechanic of 45 yrs) tried solving the problem and he says it's something inside the engine that's restricting coolant flow and I have two options A) Junk it or B) Get a new engine, though he won't help me with that part.
My friend said he'd do the swap for me for free if I buy a new engine, my current (useless) engine is a F23A4(ULEV), is there any other engine for this year that I can put in without having to change the ECU and stuff? Or does anyone recommend an engine that I should look for and what else I'd have to do if it's not the same type as my current?

 

Have you ruled-out a restricted radiator?

 

The radiator was actually replaced before he found out it was something inside the engine. It doesn't matter, i found the same engine for $550 and hopefully my friend will put it in next saturday. I'm kinda excited,after this whole mess is past me I'm going to fix up the exterior. (new paintjob, small spoiler, new fenders bc current ones are dented. Ect ect, prob going to take pics of progress and make a thread when that stuff start happening.

 

Well, cool.

I've heard of waterpump impellers that corrode away, that might have been a possibility. Bad thermostat, crud in the water jacket, or something simple like that. Still, since you found the engine I guess it doesn't matter. I'd be curious to know if you discover anything when you swap.