Got a cool new speedometer - basically 100% accurate

[belfert]

I just today got a cool new speedometer for my bus.  It is a GPS speedometer that replaces a regular speedometer.  The speedometer head is digital and has an odometer included.  I ordered this from www.nordskogperformance.com back before I started spending money like crazy with my new radiator core and such.  This is a new product for them and they have limited production runs right now.

No more worries about inaccurate speedometers because of tire size or any similiar issues.  This should be close to 100% accurate.  There are several marine GPS speedometers out there, but none of them have odometers as boats don't need them.

I'm not sure if I will get this installed before I leave Tuesday or not.  The big issue is my dash is 24 volt and I have to install my 24 to 12 volt converter before I can install this.  (I could not find a switched 12 volt circuit in my main electrical panel.)  My bus does have a Vanner to run lights and such, but it is just easier to install a $10 12 to 24 volt converter under the dash.

[Stan]

Brian: Did you ever post the solution to your fan belt problem?

[belfert]

Brian: Did you ever post the solution to your fan belt problem?

No, I did not post anything about the belts.

I talked to two local belt places and they both said a standard B97 belt would not work as they only have a 25 HP rating.  The one guy said it wasn't the fan that was an issue rather the 350HP on the crankshaft.  I talked to Jim Shepard from the board here and he said a pair of standard B97 belts would be just fine.  He recommended against going to a B98 belt as he said the tensioner probably could not take up the slack.

I ordered a pair of B97 belts from Motion Industries and got them installed Wednesday.  We had to remove the fan assembly to get the belts installed.  My friend who was helping thought hitting the starter quick would get the belts on, but I had accidently left the ignition on overnight and killed the batteries.

I ordered another set of belts after the first ones fit so I have a spare set for the road.

[Songman]

So this is an actual speedometer that goes in the dash that gets it's info from GPS? That's pretty cool. I have a portable GPS unit and also my laptop with a GPS receiver and Microsoft Streets & Trips and I have found that all of my car speedometers are incorrect, even the new cars! It would be convenient to have the true speed right there in front of you and not have to look away to a GPS screen.

[FloridaCliff]

It would be very accurate.

Not knocking Your choice, but at $499.00?

I could replace all my gauges and senders for that.

Cliff

[belfert]

So this is an actual speedometer that goes in the dash that gets it's info from GPS? That's pretty cool. I have a portable GPS unit and also my laptop with a GPS receiver and Microsoft Streets & Trips and I have found that all of my car speedometers are incorrect, even the new cars! It would be convenient to have the true speed right there in front of you and not have to look away to a GPS screen.

You are correct.  This unit replaces the speedometer head and connects to a little black box that is a GPS receiver.

It was only $350 as the product I got is not on Nordskog's website yet.  My current speedometer is wildly inaccurate in part because it uses the old fashioned four studs on the brake drum to sense speed.  The dealer I got the bus from put in several used speedo heads before they got one that even worked.  I was quoted $250 for a new speedo head and sensor and I figured that for the extra $100 I could get something that is nearly 100% accurate and needs no calibration.

I know it isn't cheap, but I thoght it was cool so I ordered it.  This was before I spent a ton on a new radiator core and such.

[maria-n-skip]

Brian,

   That is a cool product....

   Just a cautionary comment.  Our data collection crews this summer occasionally would run into
not enough birds for the GPS unit to work. Each year it gets better and your chances of being in the
wrong place at the wrong time is statistically slim.

   I will be curious how it works for you going down the road.

   A bus item that is a whole lot more fun than radiator stuff!

Skip

[gumpy]

I talked to Jim Shepard from the board here and he said a pair of standard B97 belts would be just fine.  He recommended against going to a B98 belt as he said the tensioner probably could not take up the slack.

If Jim Shepherd said to use the B97, that's what I'd do. I'd wager he knows more about belts than any local salesman.

[WEC4104]

I got to wondering about how the GPS speedo handles the initial power up.  I've had some experience with some GPS units that take a few moments to lock on to the satellites.  Let's say you stop and park your bus briefly and shut everything off.  A few minutes later you hop back in, and being already aired up, you are ready to roll as soon as you start the engine.  Is the GPS quick enough to hang with you?  What if it takes 30 seconds to lock on the sats?  Would the odometer not register the first  hundred yards of movement? 

Or, let's say the GPS stores it's last position in non-volatile memory when it is shut down.  Maybe the odometer adds on the calculated distance from the shutdown location to the next location it gets a satellite lock.  If so, what happens if you load the bus on a ferry?  At the end of the crossing, when you fire the bus back up, with the ferry trip get added to your odometer?

Yeah, I know. My mind works in strange ways. 

[belfert]

I didn't think about satellite linkup delays.  Still no worse than the handheld GPS I have been using, but the handheld is left on when fueling and such.

The odometer might not be 100% accurate, but the speedo should be and that is what I care about the most.  I have a hubodometer matched to my tire RPMs.

[belfert]

The GPS receiver has a rechargable battery to keep in sync with the satellites when the ignition is off.  Of course, this doesn't help if the vehicle is under a roof or canopy.  I just found this out.

Craig, yes I did use the B97 belt after talking to Jim. 

[gus]

I've used GPS and Loran in airplanes since day one and I found that there are many situations in which neither one worked well or sometimes not at all.

Between tall buildings, in mountain passes, inside anything including tunnels and sometimes just for no reason at all.

I can't figure out how the odometer ever catches up for distances lost between these failures since there is no way it knows what route you took. GPS essentially works in straight lines so from a failure point to the next lock on will not be accurate.

The battery is just there to maintain the user added stuff like waypoints and the last position so it can power up faster.

It is a puzzle to me why the wheel stud systems didn't work since this is a very simple system. Sounds as if the heads were the problem since there isn't much to the sender. I had planned on installing one of these to replace my cable driven one which is awful and is probably not to far from breaking the cable since it is obviously kinking or catching somewhere in that 40'+ run.

[DrivingMissLazy]

My current speedometer is wildly inaccurate in part because it uses the old fashioned four studs on the brake drum to sense speed

After reading literally thousands of posts from several different boards and for many years, this is the first time I have ever heard mention of this problem.

DML uses this system and I never had any problem of any kind for more than 15 years and 150,000 miles.

Richard

[JackConrad]

    The speedometer on our MC-8 is the original OEM with the 4 bolts in the front hub. When we bought the bus, the speedometer was intermittant (when it worked it was accurate, but would frequently quit and sometimes start again). After contacting Precision Speedometer in Phoenix and getting instructions for testing the system, we found we had a bad sensor on the wheel. We replaced the sensor and had to do a couple minor adjustments of the air gap between the sensor and the bolts to get an accurate reading. Once the gap was set, it is very accurate (compared to our GPS) and dependable. No reading until about 5-10 MPH 30MPH at GPS 30 MPH, 46 MPH at GPS 45 MPH, and 63 MPH at GPS 60 MPH.  This is as close or closer than our Grand Cherokee or Ford F350 dually. 
  However, that GPS Speedometer has got the others all beat when it come to COOL!!  Jack

[busguy01]

4 or 5 years back I decide that I didn't realy like my dash so started looking around at other options. Found Dakota Digital in Sioux Falls, SD at a car show. Told them what I had and they showed me how to do it. Now have the cleanist dash I have seen in a bus. All digital with the ability to set flash limits, either high or low, on all readouts as well as adjust speedo down to the last hair for speed. One instrutment about 1" high and 18" long has Oil press, water temp, rpm, volts, fuel, speed and odometer anlog with high head light and turn indicaters. Another smaller gage has airpressure.
Just my way -- your milage may vary
JimH