I've been chasing a leak in my AC system for about a year at this point. I've had a couple shops look at it, previous owner said the condenser was leaking, I took it to a shop and they said the compressor was leaking, replaced both of those and the drier, and a different shop is saying the condenser is leaking again. My main issue is that nobody has new condensers for NA S4s and I really don't want to buy ANOTHER used one and find out that it's leaking for the 3rd time. How hard would it be to retrofit or adapt some other condenser?

 

I was under the impression that the condenser is built into other parts in newer retrofit systems. There is a thread here recently about those retrofit systems, I can't seem to locate it though. You might have to bite the bullet and do the retrofit system.

 

so I actually have some personal experience with this as I had a fab shop install an aftermarket parallel flow condenser onto my car. Its not impossible but definetly will require some custom fab brackets and AC lines if you want to go that route which I HIGHLY recommend you do. Your in indiana but when I lived in florida the AC didnt work worth a damn and the main reason is the old style condenser just wasnt very efficient at expelling heat, especially as a r234 converted system. The day I swapped it out for a parallel flow it started working like an absolute champ.
Find a custom shop near you and see if they can fab you up some brackets and AC hoses. I can share some pictures of my setup if you want. I forget what condenser I ended up getting but I remember googling it and finding it so it shouldnt be that hard.

 

If you would, please do share some photos. Also how would I find a shop like that? I haven't had to do any fabrication like that until now, so I'm not sure who to go to.

 

Are these the systems you're referring too?

https://jp3motorsports.com/products/...tm_content=web