Speedo question
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From: Broussard USA
Speedo question
No not the skimpy swimmers drawers the thing that say how fast you go 
OK I run a GPS prety much all the time, my new on is the Garmin PDA with the built in GPS, pretty sweet! Anyway on every GPS that I have run on my last truck and my EX the speedo is right on up to 65 mph, then at 70 I am going 69 at 75 - 73 and at 80 the fastest that I have run I am only going 76. Heck at this rate I would be backing up at 100
Has any one else seen this? Is this a way for Fords to make you think your getting better MPG? I mean if you thought you were going 80 and only doing 75 you should get better MPG right? The funny part is the odo is spot on at all speeds.
OK I run a GPS prety much all the time, my new on is the Garmin PDA with the built in GPS, pretty sweet! Anyway on every GPS that I have run on my last truck and my EX the speedo is right on up to 65 mph, then at 70 I am going 69 at 75 - 73 and at 80 the fastest that I have run I am only going 76. Heck at this rate I would be backing up at 100
Has any one else seen this? Is this a way for Fords to make you think your getting better MPG? I mean if you thought you were going 80 and only doing 75 you should get better MPG right? The funny part is the odo is spot on at all speeds.
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Joined: Sep 2004
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You have a low-end "bubba" type GPS receiver. You can expect processing latency, and so you're GPS will show what you "were" going, perhaps up to 1/10 of a second. That will affect you during acceleration. Additionally, there will be a speed mearsurment inaccuracy, too. 0.1km/h would be a top end GPS unit. Sounds like your error is greater. Additionally your odometer is calibrated, but there are errors there. Finally, you're tire size may be off and slightly lower in diameter than what the odometer is calculated for.
In your case, the increasing error is a sure sign of mismatch between the odometer calibration and the tire diameter.
PSK
In your case, the increasing error is a sure sign of mismatch between the odometer calibration and the tire diameter.
PSK
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From: Broussard USA
Well first the GPS unit is DGPS and WASS and is one of the top units made, the Delome unit was not the best going but the 3 other Garmin units are about the best you can buy so sorry but I don't buy that. The odo is spot on, mile for mile with the gps and using mile markers. Also this has been the case on 2 trucks, the first with factory tires then aftermarket tires of stock size and the second with factory tires. Also no factory speedo is calibrated unless is is going into a police unit. Last tire size would be off at all speeds and be off the same amount so again that is not correct.
Now if the Garmins that I am using are low end bubba units what do you think are good ones?
Now if the Garmins that I am using are low end bubba units what do you think are good ones?
