This is a continuation of the author's study on making and using course specific diagnostic tests in college setting. First a predictive power of SAT scores on student performance in calculus classes is discussed and it is shown that SAT scores cannot be used as a useful predictor of students' performance in those classes. Lack of usefulness of SAT scores as a reliable predictor of students' performance has been noted by other authors as well. Reasons for the lack of relevance are given. The necessity of a ``home-made" diagnostic test resulted in creation of such tests and one such test is completely exhibited here. This test proves to be much more useful in gaging students' future performance, to the extent that it would be unrealistic to expect greater explanatory power of students' subsequent performance in class. Uses of the test and the resulting statistics are discussed; comparison with a similar test for statistic classes is given.