spent £25 on a rspec prv and £14 getting 5 bosch fr6ktc spark plugs,its prob the best £39 i've spent on a car.the coop has gone from a sluggish 20vt that was havin trouble overtaking cars with half the power to the full on face melter that it should be......as ya can proberly tell ,i'm a happy chappy!

cool - just make sure you're not running silly boost levels - have you got a boost guage ?

Sounds like a good idea. Have tweaked my PRV up to 1.2 bar today - might invest in a set of plugs. Do I need any special equipment to change them?

yeah i've got a boost gauge,only boosting to 1 bar in 3rd at around 5000rpm,will probably turn it up a little but keep it below 1.2 bar.
no special tools for the plugs,just a t40 torx screw driver and spark plug socket,theres a how to guide .the old one's i took out where black and old looking.well worth doin for the time and money involved