noob questions
 

I'm just wondering how reliable these cars are. if I were to buy one completely stock could I just put a fuel pump injectors and a big turbo and expect to run a mid-low 12? is a rebuild and porting job necessary? what goes into a rebuild? what do rx7 owners have to tune and whats the cost?

You have to search many hours into this forum.
There is no direct answer for your question many people try differend mods and other people go with classic and well know methods like single turbo kits look at rx7store.net for example.

Read the FAQ. https://www.rx7club.com/forum/showthread.php?t=68640