Re: A couple points ...
Both the gutless performance and wallowy handling have their roots in Californian emissions and safety laws at the time, respectively. American petrol is lower octane than its European equivalent so the engine which wasn't that great to start with was already down on power in America, and then California insisted that a load of emissions control equipment (catalytic converter etc) were added as well (such things weren't as widely used at the time as they are today).
On top of that, California road safety laws required a front bumper at a very specific height from the road, and the Delorean was too low slung to meet that requirement. In the end the company got around that problem by taking the path of least resistance and simply raising the suspension to the bumper would be at the required height, but this ruined its handling characteristics in the process.
The result was a "sports" car that could barely even get to 88 mph and rolled like a marble.