What are my chances for Cal Poly SLO Computer Science Major

I think you are a borderline applicant and CS will be a tough admit. Around a 4700 is competitive for the College of Engineering but since CS is one the most competitive majors with an acceptance rate below 10%, you should expect the accepted applicants will have a higher MCA score. You might want to select Software Engineering as an alternate major. I would assume since you live in San Jose, you are also applying to SJSU for their excellent CS program.

Best of luck.