The eastern coyote is larger than it's western counterpart. Significantly larger.
Coyotes aren't native to the east coast. They weren't introduced by NCWRC or by the Insurance industry or by the Illuminati to control the deer herds. They migrated here. Took them awhile mind you as they didn't have a direct route until we started building bridges across that big ol river that runs through the middle of the country. So they migrated north out of the southwest, through Canadistan and down through New England and the Great Lakes area to settle the east coast.
They're opportunistic predators, scavengers, and highly adaptable to their environment. They're also close enough genetically to grey wolves and domesticated dogs to interbreed and produce reproductive offspring. So in the process of their great migration they've picked up a significant amount of grey wolf and domesticated dog DNA. They're still mostly coyote, at least the ones that are several generations removed from a direct interbreeding, but they're a heck of a lot bigger as a result.
Biggest one I've seen directly was a 54 pounder that my father in law killed several years ago. I've killed a couple in the 40s and a few juveniles that were smaller. They go bigger.....
And yes one of the reasons that the red wolf reintroduction has failed so spectacularly is that the coyotes are too numerous and will simply breed them out within a generation or two.