Not sure if current tune is factory..question

[turboffr]

Just bought a used vette which had a few bolt ons and I can't be 100% certain that a predator (or equivalent) tune wasn't loaded and still there. I think it's stock but what is the risk of loading the predator performance tune without knowing what the existing tune is? Does the Predator replace or add to the existing tune? If it replaces I think I should be fine. Thanks for the help.

[mikel]

If it is tuned with another predator, your predator will not save the backup file since it will see it is a tune.