A friend of mine once bought an Audi A6, then after he got it, he regretted it because he really wanted an S6 (higher performance). Both cars were turbo V-6's.
He whined to the dealer about it, and the dealer said they could make the conversion for him. All it took was a change of "chips" and the addition of some identifying hardware. He would have to leave the car - they had to actually send the original "chip" back to Audi and it would be replaced by a higher-performance part. I forget how much it cost him, but it was enough that he REALLY had to want it.
He did it, and it worked out just as he wanted it to.
I've often wondered what the difference is among the various 2-liter turbo four's that Mfgrs offer. GM has one that has as little as 220HP, but it also has them that are over 300HP (in the Camaro, I think). All are the same displacement, turbo-four's. The same is true for VW-Audi-Porsche. Some have 185 HP (Tiguan), and some have well over 300 HP (Cayman). Is the turbo different, or is it just a matter of a "chip"?
If it's just a chip, or an easily-replaced turbo, you would think that SOMEBODY would be offering that service, because it would be worth quite a bit of money to some consumers.
Why not?