What is consider high millage on a mustang?

I been searching for a mustang between 1985-1996 and I'm wondering how long do these ford engine run for before they wear down 80k 90k 100k 150k?

If you're buying a used "performance" car, 20-30 years old, the odometer reading is totally useless.

The problem is that you don't know how much racing, or even "performance' driving, any Mustang has seen. You're taking a chance, no matter what's on the odometer.

20K miles "rode hard and put away wet" can add as much wear and tear as 100K miles, driven sensibly.

I would say 100k+

Why?

That's one of the advantages of the Mustang's front-engine rear-drive platform - You & two friends could drop-in a 'new' engine & be home for dinner. So the real $$$ is in the interior & the body. If the interior is complete & clean, & the body sheet metal is straight, start negotiating…