I have an 86 rx7 NON turbo and I want to swap that engine (13b) with a 13bt from and 87 or an 88... I was reading something on the rotaryressurection website but it did not really have what I wanted to know. I am new to the rx7 thing and It was talking about and s4 and s5 engines. I am assuming that mine is an s4, but what year did the s5 start and can I get and s4 engine that is already turbo? Is the 87-88 and s5 engine? I really just need to know what things I am going to have to swap on my car and whether or not it is a matter of taking the old one out and then just bolting the new one back in (connecting everything of course). Some help would be great. Thanks