i know it s a stupid question, but when MUST you change tires when you want to drive spiritedly? when the rubber is flush with the blocks inside the tread? when the rubber is flush with the little arrow on the sidewall? or before all of these points?

i havent experienced any trouble with the tires, but im worried that i'll be on a hard turn and it'll just slide out.

 

In general, when the rubber is flush with the treadwear blocks/bars. But some tires will start to show poor handling characteristics before this point.

I say replace your tires when they hit the bars, or when your car begins to feel unsafe; whichever comes first.