Tilt is normally used as a verb meaning to move something "off of a level plain" . However, Ramp is most often used as a noun but may be used as a combination verb. For example: I am going to "ramp up" (meaning to increase) my efforts.

‘Tilt’ is usually a verb meaning moving an object in a slanted direction. Example: “Don’t tilt the glass, or you will spill the water.” ‘Ramp’ is an inclined object used to make reaching a higher place easier. Example: “My friend uses a wheelchair, so we installed a wheelchair ramp at his house instead of stairs.”

Tilt as a verb has the connotation to be slightly off level at an angle. For example, if you tilt the chair it is sitting on one or two legs. Tilt generally implies an unnatural and unstable angle. It does not always have to be unstable though. If your painting is hanging tilted it is hanging crooked. Tilt could also be used as a euphemism or to express bias. For example, poker players often go 'on tilt' after being outdrawn in a hand they should have won. Here you can see how the connotation is still the same, the natural disposition of the poker player is altered and so their emotional state is 'tilted'. A ramp, as a noun, is usually some sort of permanent or semi-permanent surface used to connect to planes at different heights. For example, you can have a ramp next to stairs for wheelchair accessibility or you could have a built in ramp on a moving truck to roll items into the back of the truck. There is an idiom, 'ramp up' which means to increase production or productivity, but this is unrelated to tilt or ramp in the normal sense.