[chris15]

I wouldn't personally suggest an engine swap as the PT has a ton of sensors and the computer is locked up tighter than Fort Knox. It would be extremely difficult to make sure that all the sensors on your new engine play nicely with your computer.

You can increase the compression of the motor by decking the block, swapping pistons, etc. The cost, however, when compared to the result, will leave you wanting more-- trust me. On the other hand, if you have a limitless amount of cash flow, (which would beg the question: why a PT Cruiser?) then you'd be much better off following the consensus in this thread: sell your N/A and get a turbo/GT.