I'd estimate 32pppg for maple syrup. One quart probably weighs about 2.5#, maybe a little more. So in a 1gal batch you're looking at raising the OG by 80 points.
I made a brown ale with 2qts maple syrup in a 5gal batch - it was pretty awesome but took at least 6 months for the intense (almost gaggy) maple flavor to mellow and marry with the rest of the flavors. It was like an Imperial Stout when it was done.
Perhaps you need to think this brew through a little more?