Im just waiting for the call from Sonic;
"Stu, ive run out of fuel on the M6 doing that test"
you just know it will happen. 34 mpg i got which is pretty fookin good. the question is if you have two cars same spec on greys, running both at same speeds one doing 15ish mpg which isnt uncommon for greys and one doing 30ish mpg [ closed loop ] where is all the extra fuel going? bore wash? fouling valves and pistons?