<P> A few roads that weren't Interstate Highways but were built to Interstate standards were redesignated as Interstate Highways to qualify for the increased speed limit: </P> <Ul> <Li> Kansas petitioned the Federal Highway Administration on May 14, 1987, to "designate the turnpike as an Interstate Highway between Topeka and Emporia". This Kansas Turnpike segment had existed since 1956 without a numerical designation . Interstate status was granted, Interstate 335 was designated, and the 65 mph speed limit signs went up . </Li> <Li> Interstate 88 in Illinois had previously been designated as Illinois Route 5 . </Li> <Li> 50 miles (80 km) of the Maine Turnpike between Portland and West Gardiner were designated as Interstate 495 in 1988 . The designation for this segment was changed in 2004 to Interstate 95 to simplify the Interstate numbering scheme in Maine . </Li> </Ul> <Li> Kansas petitioned the Federal Highway Administration on May 14, 1987, to "designate the turnpike as an Interstate Highway between Topeka and Emporia". This Kansas Turnpike segment had existed since 1956 without a numerical designation . Interstate status was granted, Interstate 335 was designated, and the 65 mph speed limit signs went up . </Li> <Li> Interstate 88 in Illinois had previously been designated as Illinois Route 5 . </Li>

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