CheeRS guys I shall keep them normal for top speed and handling and maybe lower them a bit for 1/4 mile
if your running stock road tyres your not gona come anywhere in handling or 1/4mile mind as others will have good tyres so grip, so maybe not worth arsing round with pressures really.
I've ran a 13.8 at brunters with 17's and crap Avon tyres I now have really good Yokos so we'll see what happens.