abbs you have just answered ya own question mate

all cossies need to run super, tbh they really really need leaded 4 star but that aitn gonna happen

if its not mapped for the boost then its not gonna have the fuel map there, greens run lean on a cossie with a t34 at 1.73bar, well mine does anyway, thats on optimax and at 6000rpm under load

running normal fuel will make it pink, thats why ya use super as it stops the pinking

tell ya mate that even though his car will be sooooooooo much better for throttle responce and power what is actually happening is hes cylinders are getting soo hot that the fuel is sparking from the tip of the plug and the temps of the engine BEFORE the spark

thats when the cossie engine melts

i know ya get a hard time on here, its hard work for lots of people tbh, but in the end people like gareth ect do know what there talking about and they do mean well

so to recap, he needs optimax, fresh optimax too as it goes off after a month ive noticed and also run the correct boost for the map, anymore OR any less and the car will either melt or dilute the oil with fuel