Exactly this. Turbos are dead at 4500. I understand this is the "first tuned Z" so it is worth something, but the way the HP and Torque just peace the fuck out at 4500 means new turbos are going to be required nearly instantly. Ethanol will bump the curves up but the curve will look the same.
I don't know the answer to your question, but I do know that if you bought the car for any other reason than you absolutely love the car, I don't think you'll get much sympathy from this forum.
Just an observation on past discussions on resale value here already, and the general consensus is...
Brought the car out to Midwest Bimmer Fest over the weekend. It was the first time it's been out since the EOSpeed turbo kit's been in. I haven't made a dyno appointment yet, but I know it's running 9.7 on low boost.
We still have a lot of finishing work to do: powder coat the charge pipes...