Friday, August 17, 2007

NEDRA Pictures

Going to NEDRA at Portland International Raceway was my first major excursion in the 914 since both the flywheel was balanced and the clutch was properly adjusted. The car handled very well and cruised on the freeway without much problem. I did get up to 65 but kept my speed mostly at 50 to not pull too much current while breaking in the batteries.


Here's the wait in line for the ticket office at Portland International Raceway. I felt proud to not have to waste gas while idling in line.

I spent most of the time answering questions about the 914 so I didn't take too many pictures or see too many races. Maybe next year I'll try it out.


Here's a more serious electric drag racer. As you can see, the original engine compartment up front is fairly barren. The Zilla2K controller sits in the bottom.


Here's looking in the rear window where all the A123 batteries are. There are probably more pounds of high-current Anderson connectors than batteries.


Here's the "purist" control cockpit.


While not a racer, this entry was rather interesting since its electric motor didn't power the wheels...


but it powered a huge fan on the back of the car.


Here's Miles' antique vehicle that he brings to most of the OEVA monthly gatherings.


Miles uses Hawker Genesis batteries to power the antique vehicle. Much lower maintenance than the originals!


This is a Honda Civic Delsol conversion done by Chris Brune who helped me understand how to drive my electric car better using lower gears and higher RPMs.

That's all the photos I took. There were many more vehicles and many fun EV drag races. Just as I left, one EV drag racer had just spun out into the wall. Exciting times indeed.

1 comment:

pjorg said...

Tim,
A few thoughts on your vibration problem.


Vibration analysis and is a well defined science which is used in the machinery business for many years. The essence of it is that by looking at the vibration signature and amplitudes which is the spectrum of frequencies that occur and in the three different planes of any rotating equipment, it is possible to correlate it with the know causes of vibration such as imbalance, misalignment, looseness, bearing defects, gear faults and motor faults. The different planes include vertical, horizontal, and axial. This is typically done using an accelerometer mounted on the rotating equipment which is connected to spectrum analyzer. In your case if you are were to have an accelerometer mounted on the motor and gearbox and then run through different speeds while recording and then plotting the different spectrums it is possible to determine if the vibration is an imbalance issue, an alignment issue, a bearing issue in the gearbox or maybe a critical speed issue.

I have listed a few vibration resources below which may give you some more insight into the problem. Perhaps you may even find a vibration expert Portland who would be willing to put a couple probes on for a few minutes to give you, ( actually all of us who are concerned about this) a hint of what is really going on.


http://www.earthdyn.com/Vibsum.html

http://www.unitechinc.com/pdf/IntroductiontoTimeWaveformAnalysis.pdf

http://www.plant-maintenance.com/maintenance_articles_vibration.shtml