I want sample to match my grid but not change tempo...

Alright, I import a song from a friend, cut it up, get the samples I want, such as a guitar riff. 

Obviously it's not 120 BPM. I find out it's 97 BPM. I lock the track SMPTE so that when I change the project it doesn't change the tempo. Done, works fine. 

But when I hit flex time on it, because I'm making it a loop and the song isn't recorded to a click track so it's somewhat out of time, then it starts playing at 97 BPM, of course slowing it down. 

If I change the region from 120 BPM to 97 BPM obviously that slows it down to. 

Is there anyway to use flex time on imported files to make them into loops without slowing them down like that? Or do I have to just slow them down and then bring the tempo of the region back up to 120? 

Not really sure what the problem is here, but let me give you an example:

Let's say your project is at 120. Now you have a song that's at 97. You chop the song into small loops. Regardless of their length, their tempo is 97. You lock the SMPTE of those regions, change the project's tempo from 120 to 97, unlock the SMPTE (not sure if you are unlocking it after you changed the project's tempo, but you need to unlock it). Now if the the song you imported is REALLY at 97, everything should be playing with the click, you just align the samples/loops to the grid. 

If for some reason there's a slight difference, maybe that region is not working 100% as a loop. You have to make sure that when that chopped section is playing in loop, really sounds like a loop. To check this, double click the region, select the tab File instead of Track, click the loop button on the bar and play it. See if it sounds good when it's looped. If it does, then you just need to really align it with the grid. Do this by moving your mouse to the top bottom left or right of your region and once it goes from a pointer to a square bracket, press Alt/Option on your keyboard and it will look like a square bracket with some lines on each side. While holding Alt/Option, click the region's border and drag it to align with the nearest grid division. That will extend the region or make it shorter. Do the same on the opposite side. Now you should have a perfect loop.

Hope it makes sense.

Once you do this, you can then activate the Flex Time and if you change the tempo of the project, it will change the tempo of the region as well.