There are legible 600dpi black and white tiff images of Detroit maps from various years now available at the Internet Archive. On the left hand side of the following pages select the "All Files: HTTPS" link. From there download the file ending in "_tif.zip". I've included the file-names I know for some of the maps that can be found in the zip files, otherwise you might want to download the PDF versions of the books to locate the page number of various maps.
Atlas of Michigan 1873
http://www.archive.org/details/27465....001.umich.edu
[[1873 map of Detroit) 2746566.0001.001.umich.edu_0132.tif
Illustrated historical atlas of the county of Wayne, Michigan [[1876)
http://www.archive.org/details/39281....001.umich.edu
[[1876 map of Detroit) 3928152.0001.001.umich.edu_0056.tif
[[1876 map of Grosse Point) 3928152.0001.001.umich.edu_0013.tif
Atlas of the City of Detroit and suburbs [[1885)
http://archive.org/details/3929071.0001.001.umich.edu
These maps have footprints of buildings with many of the larger ones identified.
Detailed official atlas of the of Wayne County, Michigan [[1904)
http://www.archive.org/details/39281....001.umich.edu
[[1904 map of Detroit & Environs) 3928153.0001.001.umich.edu_0014.tif
[[1904 map of Gratiot & Grosse Point) 3928153.0001.001.umich.edu_0020.tif
Detailed official atlas of the of Wayne County, Michigan [[1915)
http://www.archive.org/details/39281....001.umich.edu
[[1915 West side of Detroit) 3928154.0001.001.umich.edu_0028.tif
[[1915 East side of Detroit) 3928154.0001.001.umich.edu_0033.tif
[[1915 map of Detroit) 3928154.0001.001.umich.edu_0030.tif
[[Private Claims) 3928154.0001.001.umich.edu_0014.tif
[[1915 map of Grosse Point) 3928154.0001.001.umich.edu_0046.tif