Preheat the oven to 350°F (175°C), with a rack in the lower-middle position.
In a bowl, combine the graham cracker crumbs, sugar, salt, and cinnamon. Stir in the melted butter until the crumbs are evenly moistened.
Press the mixture evenly into the bottom and up the sides of a deep 9-inch pie dish. Bake for 10 minutes, then set aside to cool slightly. Leave the oven at 350°F (175°C).
In a large bowl, whisk together the pumpkin purée, sugar, salt, cinnamon, nutmeg, cloves, ginger, and allspice.
Whisk in the lightly beaten eggs, then gradually add the whole milk and evaporated milk. Mix just until smooth.
Place the pie dish on a rimmed baking sheet and pour the filling into the crust, leaving a little space below the rim. If necessary, bake excess filling separately in an ovenproof ramekin.
Bake for approximately 55–70 minutes, checking from around 50 minutes, until the edges are set and the centre still has a gentle wobble. Loosely cover the exposed crust edges with foil if they begin to brown too much.
Cool on a wire rack, then refrigerate within 2 hours of baking. Chill for at least 4 hours, or overnight, until fully set.
Slice and serve with whipped cream, if desired.