Hi there fellow scooby owners, im due to service my scoob for the first time since i bought it, but when i went to change my spark plugs it turns out the previous owner had used odd plugs!! Its a 2.5 sti short block with td05 turbo, 720cc injectors, uprated fuel pump to name but a few mods and is due to be running around 350bhp safely. So the question beckons what would be the best plugs to buy? bearing in mind the overall aim is for 400+bhp. Ive been told by scooby parts that the ngk pfr7b plug is good for 300+ but thought id ask my fellow enthusiasts as well. Any help will be greatly appreciated thanks guys