The easiest way to answer this question would be to compare your GPA percentile to your SAT percentile. 1870 is about the 85th percentile. The problem is that there is no standard GPA percentile scale since every high school uses a different system, and every high school has a different level of competition. So if you got a 4.35 GPA at New England Greek and Latin Preparatory Academy, where the average GPA is 3.0, an equivalent SAT score might be 2300. If the 4.35 was from Inner City Public High, where 50% of students drop out, an equivalent SAT might be 1400.
The definition of "good" could also vary. If "good" means getting into the less-competitive public university in your state, where the average GPA is much lower, your 4.35 could be enough to get you admitted even if you did much worse on the SAT. If "good" means admission to the highly-regarded public university in your state, where you'd be competing with serious students, you might need a 2000. To get into one of the elite private universities (Harvard, Stanford), where practically everyone admitted is a straight-A student, you might need a superior SAT score like 2350.
Of course, none of these take into consideration all of the other variables in admission. Are you a member of an underrepresented minority? Are you a star athlete? Do you come from a part of the country that doesn't send a lot of people to Harvard (e.g. Wyoming)? Are you a published author or scientist? Are you a legacy? Did you win the Westinghouse prize? Do you speak Swahili? All of these may factor into admissions decisions.
In the end, the easiest thing to do is talk to people at your school with similar GPAs and see what they scored. If your scores are equivalent or better, you're in good shape.