[olddog]

With a lot of knowledgeable Mark IV people in this thread, I have to ask:

So many complain about the low powered 5.0 Mustang engine that came in these cars. It is fairly easy to drop a 347 storker EFI engine in producing 425 Hp. Now the car would no longer be under-powered, and it can easily be returned to the original condition, by putting the original engine back in. Nothing is cut up or permanently modified in the process.

Now to the question.
Are these cars so valuable, that they must stay untouched to prevent them from loosing value?

I understand an untouched anything at a collectors auction is worth twice as much as the identical car with high performance mods and a $30,000 perfect paint job. But is a Mark IV really collectible and worth keeping original un-touched?

This is not a sarcastic post. I am honestly curious as to what the answer is.