Whats my engine worth and what is the biggest baddest engine I can put in my boxster

[AKnowles]

I think he wants not what he asked for originally. Based on his remarks, I'd say he wants the least intrusive, least expensive, best bang for the buck alternative and for that he should probably give up everything else and just go with dropping in a used engine from a similar model 996 S. From what I recall these are more horsepower and can be fitted without a lot of work.

For myself, if I were going to spend any modey on a new engine, I'd seriously consider sending it to Jake for a 3.6 DIY upgrade and if I had the money let Jake go to town on it. Otherwise, there is just no reason to spend money on a bigger engine.