Grip is a function of the friction coefficient and resistance to tyre distortion, the grip coefficient is a fixed ratio determined by the rubber compound the components are force applied down v force required to break the frictional grip , for a road tyre its normally about 0.9 , tyre distortion effects how much the tyre will crab away from the direction of travel when put under side load whilst rolling and it's mainly influenced by aspect ratio.
As a summary
CoF determines the cornering force required.
Tyre aspect ratio determines the rate at which it will break away, an 80% tyre will gradually break away where the equivalent 45% tyre will break away more suddenly.