Speedo correction

[muchco]

Hi, I just installed an new BRP speedometer and have checked it against my GPS. It consistantly reads 3 mph slower than my GPS reading. I used my original speedo pickup as I just purchased the BRP speedo and not the pickup and hose. My old speedo with the current pick up was within 1/2 mph of my GPS. I changed all my gauges. (just in case your wondering why I changed a working speedo). Is it possible to correct the speedo or make it closer by altering and or changing the pickup? Thanks for your time.

 

[Chris1956]

Re: Speedo correction

If you drill out the hole in the speedo it will read higher. However, you may make it very inaccurate, if the hole is made too big. 3 MPH is pretty close. Just add three to the reading in your head, would be a better option.

 

[muchco]

Re: Speedo correction

When you say drill out the hole, I trust you mean on the speedo pick up and not the speedometer it self. It may be worth the $10.00 to try a new pickup as well, or as you suggested just add 3 mph to the indicated speed. Thanks for your response.

 

[JB]

Re: Speedo correction

Remember this when comparing a pitot speedo with GPS readings.<br /><br />It is entirely possible that both are correct if there is any water movement.<br /><br />The pitot speedo only measures speed through water. The GPS measures speed in space.

 

[muchco]

Re: Speedo correction

Thanks for the info.