no.
we talk about stunt being modded if the vehicle is not orginaly in game, the performance of it are changed (handling is changed), if u use it in a place it cant normaly go (tho it doesnt really matter anymore), if its stuck in a way you woudnt be able to do without additional tools, if you use any tool that helps you in a dirty way

for ex SACCs + button or speedhack etc. you also cant affect gravity and such
its often said that if stunt cant be done on ps2 then its modded but other map mods are allowed