gps speed vs speedo

[kevinfish]

while fishing with my friend yesterday out of his new boat we noticed a difference in the speed readings.at top speed the factory speedometer said 55mph and the gps on his fishfinder said 52mph.has anyone else seen this or is the factory speedometer off?

[Danny]

Kevin,

My experience has always shown me that the boat speedo is usually off. It is generally a water pressure driven device. I always go by my GPS. Otherwise, I think my boat ... a TR21 hit the 95 mph mark... LOL... well not that fast, but it has always shown higher speeds than my GPS, and I have a little more faith in the GPS speed.

I hope this helps,

Tight lines and God Bless

Danny

[mattplapp]

I've never seen one accurate. There are too many variables that mess up factory Speedos. The GPS is your only way to go.

Matt

[MarkW]

Boat speedo's are never accurate. Mine used to peg 80---but GPS was always about 72-73.