Engine dyno for EFI project

[Andrew Dennison]

Jonathan R. Lusky wrote:
> Really high end commercial dynos will have a "torque cell" between the
> engine and the absorber.  The torque is a shaft supported on bearings,
> with strain gauges on the shaft and slip rings to make the electrical
> connections.  Pretty accurate, very high dollar.
> 
Why not mount strain gauges on the gearbox input shaft, or the 
tail-shaft.  You can get around 5% accuracy (or better) in the basic 
strain reading and if you use a few equations and know the material 
the gauges are mounted on you can calculate torque.  The tricky part 
might be building some reliable slip rings.  You can build a strain 
gauge amplifier quite easily.

This could be a true on-road dyno, get instantaneous torque readings 
under acceleration or tune under constant load (feet on brake AND 
accelerator to maintain speed).


Andrew

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Andrew Dennison - Research Associate
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