4. All JDM Z's are restricted. You can de-restrict it with a speed de limiter made by HKS. Search on the forum will give more info. There are a couple of types depending if you have a manual or triptronic, typeII is for manual and type III is for triptronic. They go on ebay for around £125
and can be fitted by yourself but if not a company like TDI will be able to supply and fit.
Info on TDI is in the forum discount section