I have a quick question?

ChipsWithDips

Do you both have same transmission type, same trim level?
Same wheels and tires?
Same amount of wear on the tires?
Were the tires on each vehicle inflated to the exact same PSI?
Did your friend have an oil/spark plug/air filter change recently and you didn't?
Were the oil and coolant temperatures the same on each vehicle during those runs?
Was the ambient temperature/humidity/barometric pressure exactly the same when each car was run?
Did they strap down the cars to exactly the same tension?

Lots of **** can cause a difference in dyno reading, I wouldn't sweat it too much.

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