Sex Advice from Men-I seriously need help.

My boyfriend of 2 yrs. has trouble lasting more than 3 minutes when we are having sex. I don't want to hurt his feelings or make him feel insecure by mentioning it. I just don't want it to be an issue-I'm afraid that if we have "the talk" then that's all he'll be able to think about when we are intimate. What can I do in a loving and nurturing way to help him last longer without him knowing that's what I'm doing. I'd rather do nothing at all then start my engine and keep it in park. Please no crank answers. I seriously need help.