Jackie Stewart 's new engine was just not performing properly .
Jackie Stewart could not pass Pedro Rodriguez 's B.R.M. but John Surtees , in Jackie Stewart 's new car for the first time , was beginning to come up .
Jackie Stewart 's new engine was just not performing properly and he could not pass Pedro Rodriguez 's B.R.M. but John Surtees , in his new car for the first time , was beginning to come up .