I assume your question has more to do with curiosity than anything else. You didn't say which BAMA tune you had, hopefully it's their 87 octane tune and not one designed for 91 or higher. Personally I don't have any problem with running 87 on a show room stock Coyote in everyday driving, but even show room stock if I know I am going to hammer on it I run at least 91 in order to prevent any possibility of detonation. The Ford track key is fairly conservative as tunes go and even they require a minimum of 91 octane. As for the horsepower numbers, well the only numbers that really count are time slips/lap times. If you put the car on a dyno make sure you ask what correction factor was used. Every dyno/operator uses a correction factor to equalize variables such as temp.,humidity and altitude/barometric pressure. The hot rod industry loves to use the old correction factor used by the factories in the '50's & '60's since it gives more impressive numbers. If you can get to a drag strip make at least three passes and average your trap speeds. ET has more to do with the chassis set up, trap speed is horsepower. You will also need an accurate weight for your car with you in it as raced. There are plenty of horsepower calculators online you can use to find your horsepower. Here is one using my own car as an example. Weight with driver and 1/2 a tank of gas = 3725 lbs. Trap speed 111 mph. Trap speed divided by 234 [ a constant ] = .4743589. .4743589 cubed = .1067385. .1067385 x 3725 [ weight ] = 397.6 HP.