I have bought the MY01 WRX 40k on the clock one owner FSSH . it has no mods what so ever. so over the next week I will be looking to put a few more horses in it .

Help here would be great ! what would be the first thing I should do with the car ? filter ?

 

Congratulations!

Filter, back box and centre decat is a good starting point, but don't expect too much unless you go for a remap... early bugeyes can be pretty 'lumpy' (as my '01 is) which can be much improved with a remap.

Have fun!