its stable at those speeds provided you dont make any lane changes or have to brake for something suddenly or get a blow out or a flat.

It is not "fun" and not safe but I've done it as well so I know where your coming from. I don't suggest driving that fast for any amount of time because its way too fast for the car and way to fast your your typical driver. I don't even want to know what your braking distance is at 140mph lol....I just let off the gas and let the car slow itself down.

Otherwise at around 130mph the car starts to feel like its floating and at 140mph the front end is very light, its around 140 that you realize your going way to fast for your stock suspension and that you really hope nothing gets in your way on the road.

You can go that fast and not die btw, its the slowing down part from losing a tire and hitting some freeway wall that kills you

Engine will not overheat either, but your gas mileage sucks, and going that fast (140mph) isn't worth the 30 seconds you could save on going 120mph instead. Over 100mph unless you can keep a very high average speed its safer to just drive around 110-120mph.