If you do decide to let him work on it, suggest to pull the heads off with the motor IN the car. There's no reason to pull it completely out of the car to pull the heads off. That's a waste of labor and ends up costing you extra money. That being said, I agree with Dave about trying higher octane first. It's easier to go put 20 dollars worth of high octane fuel in it than to pay someone 20 hours worth of labor for no reason.