Alastairant,
"just got a mk4 golf 1.4s and am looking to get a little more power out of it"
Enjoy the car for what it is. Golf Mk4 is a great car, yours is easy at the Petrol Pumps. Drive it well

, and it will do a good job for you. Change plugs every 10k, oil and filter as well, and buy good quality tyres for handling. Keep the car looking sweet, clean it regularly, a nice clean interior is always good to get into.
As other folk have said, keep your £300 for another day. Golf's are great cars, and you have one of them

.