First of all, this is an ancient laptop with a Penryn processor. There is absolutely zero chance of it ever having any Core processor, let alone an i7. Secondly, very few laptops, especially back then, supported processor upgrade at all.
For a final answer, you need to talk to Acer. In order for a processor to be used, it must be board, socket and BIOS compatible. Since the design of the board and BIOS are in the hands of the manufacturer, only the manufacturer can tell you whether a processor is supported. Don't let them try to pass the buck; only they can answer this question.
Sorry I didn't have a better answer, but this is the reality of the situation.