Out in my rs turbo tonight , the engine spec is ,grs intercooler,bayoo chip,piper cam and pulley , all rebuilt 8000 miles or so ago anyway , my car runs perfect (usually) nut a mouse fart out the engine ,car runs 15 psi and made 158 bhp @wheels and is set up ,fueling is all sound ,, and raced a astra turbo tonight and was sitting at 135 ish and engine revs started to die on me basically engine was losing power and i new something was up pulled over and stoped engine as was struggling to keep running popped bonnet and my oil cap had blew off resulting in some oil over my rocker cover , cleaned up and checked oil etc, all ok but when tried to start again , sounded as if was running on 3 cylinders and was smoking out my exzaust pretty bad anyway toed it home and going to get engine apart on sunday engine starts but struggles bad , sounds not to bad , but has a real reek of smoke when running to cap it off my girlfriend told me she stuck a £10 worth of normal unleaded in it this was set up to run super! has this been the factor in my engine blowing? whtat uz think damage is? what uz recommend buying ? any help appreciated