So I'll be getting a 89 RX with a bad engine hopefully soon. Now I can either repair the EA82 in it or I was thinking about swapping in a new engine. So I have a few questions about that. First: Can you swap a EJ engine into a RX? Second: If I can swap a EJ engine can I use a EJ22T block with a EJ18 crank and will that destroke the engine? Third: If previous 2 questions can happen, if I were to put EJ205 heads on my EJ22T frankenengine what would my compression ratio be around?

You will find most of your questions answered in this sub forum. If you look for threads started by me, you will the write up about the EJ22T swap I did in my 89 RX.

If your smart, you will leave the engine stock as it has plenty of power for the RX.

IIRC......EJ18, EJ20, and EJ22 all use the same stroke crank, 75mm.  Just the barrels/bore size changes.

 

An EJ22t would be great......Turbone did one in his RX.

 

Pretty sure ej205 heads would increase compression slightly.....maybe to 8.7~9.0 or so......a bit high for alot of boost....

Edited August 9, 201411 yr by Gloyale

Well I mean I do have a STi block siting in my garage right now that I could build. I know SJR lift makes an adapter plate and flywheel to swap EJ engines into the RX. I'm not looking to run a crazy amount of boost probably 12 at max. So I'm thinking destroked STi block with 205 heads. Hybrid destroker here we come!

12lbs is getting up there for boost.

 

stock they make less than 10