Is this a good 40 time ?

The average 13 year-old runs between 5.4 and 5.8 so you're on the slow end of average.

Remember, the best way to prove yourself is through actions, not words. My best advice for you is to work hard and perform very well in practice every day. In addition, what you need to do this autumn (and every offseason) is eat healthy, exercise by doing weight lifting, and either jogging or going for a long run every day. If you do these things, you will get faster, stronger, and into better shape, which will greatly improve your chances of becoming a successful, top notch defensive end in high school football, who could go on to play college football.

By the way, your chances of playing college football depend on your performance in football during your senior year of high school. If you perform very well in football this season, you will greatly improve your chances of getting recruited to play for a college football program

Personally, I do not believe that your best fit is at defensive end. Based on your height and weight, as well as your 40-yard dash time, I believe that the best fit for you is at strong safety. For your age, you have the ideal size for a middle school/high school freshman strong safety.

My best advice for you is to work hard and perform very well in practice every day. In addition, what you need to do this month (and every offseason) is eat healthy, exercise by doing weight lifting, and either jogging or going for a long run every day. If you do these things, you will get faster, stronger, and into better shape, which will greatly improve your chances of becoming a successful, top notch strong safety in football.

it's good for 13 year old i checked the chart and your above average for your age

I think this is slow. You need to get below 5 sec.