Can you remap a mk1 golf gti 8v ? Stupid question?

I have a standard golf gti and want to know if I can remap it 

If its a standard tintop , then no, not in the accepted sense as there is no ecu to remap. I believe it used to be possible to buy a little box ( name escapes me) that provided some spark adjustability, and the injection system being mechanical does allow for some adjustment.

Agree, being relatively old tech you can't simply plug in a laptop and release +50bhp.

The only way is to physically change or add bits, twiddle timing and CO levels, fit larger throttle bodies, different WURs, grind out ports, swap to a hotter cam shaft etc.

Thank you that's really helped me actually.  I'll get a timing light and make sure everything's perfect. I've completely rebuilt the engine on my mk1 gti cabriolet… I'll take that advice onboard and set about it