I'm pretty sure you have to send the ecm in and have it reprogrammed.
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and the amount of hp bump varies from motor to motor. some they can get a pretty good increase some not so much. probably won't see much in top end speed increase. 3-4 mph on that motor is all I'd guess.
Stay away from any of the "Foolers" or Chips for outboards. Go with Simon motor sports ECM reflash. The ECM needs to be sent into them. I had it done on My Yammy F150 a couple years ago and it was well worth it for the added fuel economy and better running and smoother performance overall.
Cost was $600 plus shipping IIRC. I will recoup the 600 bucks in fuel savings alone within a few years.
What hull did you have the F150 on? Did you see any speed gains?