took the car for a longer run 60 miles or so today, after pushing the engine a couple of times 5.5k revs the was a couple of little misfires but at the next lights i could see burning oil off the exhausts. temp seemed ok and fans not on. the on another hard blast all ok until back to gentle drive when i started misfiring amd the engine cutting out. temp shot up so slowed down and car returned to normal. back in garage it appears oil is blowing out of the filler cap. it doesnt look like gasket gone and now the car is behaving again other than a weep from the filler. this is beyound me....where do i start chaps?