it is a big engine bay, some people have put LS1 corvette engines in them
5.4
yes
yes, however you may need to adjust the wire harness to fit.
The 89 is an s5 and the 87 is an s4 It will fit but might take minor modification.
Depends, which engine is in the 85, 13b or 12a?
An odd stud pattern on the s3 1984 rx7 . It's 114.3x4...
No the engines are not the same.
Yes. If you have an RX7, then it already has a rotary...and if it is a 1997 then you have a rare Japanese model.
yes
Yes, if the engines are the same size.
Yes the are the same engines. That is a direct bolt in