When I bought my boat the gentlemen who had it before me said the GPS speedo was calibrated for Washington state and could be off by a few mph. I have never heard of this. I would think that it would pick up the data from the sattelites and calibrate itself to its new location. It is a Gaffrig GPS Speedo on my 97 29 Fever. Anyone have any insight or input?

Never heard of that either. In my last boat I installed a Livorsi GPS speedo and right out of the box it read dead on with my GPS.

I am retired Army as well and whenever we went anywhere we never had to recallibrate any GPS equipment for the location. Now we had to calibrate in the GM angle (difference between magnetic and true north) and make sure we had the proper mapping DATUM. I am pretty sure it will read GPS speed correctly anywhere you go. I am bringing my handheld with me this weekend as a backup to see if there is any difference.

He wasn't trying to convince you it was really faster than what the GPS said, was he?

No he was saying the GPS Speedo was reading faster. I checked it this weekend and it is dead on with my handheld. Now I just need to get my 30P Bravo 1s back from labbing (this week) so I can check my top end. I can get 84 with the 26s hitting the limiter at 5400. I was getting 92-94 depending on load with the old 30P I had on. I will be happy if it runs 95-96 fully loaded with fuel. I like to cruise at about 55-60 so that is what I was really after was better midrange and not so much top end.