TeamD Adventures

4 Responses to “AZ1000 Day 4”

1. Jeff McMillen Says:
   May 15th, 2009 at 6:54 am

   Are you using VSS for the odo input or an external wheel spinner? I had similar fluctuations using VSS on the WRX with both the Alfa and the Timewise and was never able to get a consistent reading until I used the magnetic sensors. I had an email chat with Jack C. about it but we never got to the bottom of the problem.

2. Marinus Says:
   May 16th, 2009 at 7:02 pm

   Jeff, we were using a regular Timewise sensor (barrel style), bolted to a R. Jones custom-made hub mount. It’s very similar to an EZ-pulse, just smaller in diameter. Revere’s used this style successfully since the ’98 Alcan.

   In our case, though, there was something awry. The first factor we saw on Monday morning was ~34000. That’s a factor more befitting a four-magnet system than a two-magnet system (but that didn’t occur to us ’til later in the week). After some time on gravel the apparent factor dropped to ~27000 — which corresponds to a 5-magnet system (!). 27000 was what we ran Monday p.m. — Thursday, though it was a lot of work to run with it.

   On Thursday night, in a frustrated rage, I went back to basics. After a visit (or three) to Home Depot I mounted the sensor to the rear control arm and put two magnets on the wheel. Boom! The factor was now ~69000 (fitting well with the tire diameter) and the mileages were rock-steady on Friday.

   I can only surmise that the Timewise sensor was giving double (triple?) readings from the magnets in the hub-mounted unit — Jack C. describes a “bounce” situation if you try to read a bar-shaped magnet, giving two pulses for one pass of the magnet. Why that situation would come and go I can not say…. heat of the day changing magnetic potential? It was, as you can imagine, HOT.

3. Marinus Says:
   May 17th, 2009 at 12:02 am

   Re: “one car didn’t finish due to mechanical problems” — read: new Jeep Patriot not all that happy about 1000 miles running in 4WD. The driver’s description sounded like front diff failure, and/or transfer case seizure. Joy.

   The AZ1000 toll:
   (2) cars broken down on the way to the rally
   (8) flat tires
   of those, (5) destroyed tires
   (1) front diff
   (1) minivan on two wheels
   (1) Contour SVT exhaust system
   (2) angry bicyclists
   (0) traffic tickets (AFAIK)

4. Renee Says:
   May 17th, 2009 at 11:11 am

   Also
   (1) GPS fried in the heat
   (1) Alfa Clock fried in the heat
   (1) Angry local in a truck/trailer combo going with racer (his word) traffic
   (1) car broken down on the way to the rally and DNS at all
   (1) Plastic spare tire cover which came off and skittered across the pavement