Torque measurement

[Matt S Bower]

Clive Apps Techno-Logicals 416 510 0020 wrote:
> 
> >
> > Since the motor mounts are connected to the block , you need to rotate the
> > block to compress the load cell not the crank.
> > The hardest part with this method is figuring out the scale in foot pounds.
> > Usually load cells are calibrated with certified weights hung from a known
> > length, usually a 1 foot long bar, hence 'foot- pound'  I don't know how you
> > could calculate the moment of movement that the block would place on the
> > load cell. I would guess if you bolted a 1 foot bar on the engine at the
> > center line of the crank and placed a 1 pound weight on the end of the bar,
> > you would be able to calibrate the load cell out put for 1 foot Lb. Of
> > course you would
> > want to cal it to 300 ft.Lbs or what you think the engine would put out. If
> > you use a 2 foot bar then 1 pound on the end would apply a force of  2 foot
> > Lbs. This would save some cal weight. Your idea is  excellent  and should
> > give some good results. Another way to read the torque would be to connect a
> > load cell to the block about where the front freeze plug is, and the other
> > end to the frame. This will make a solid motor mount that might damage the
> > Trans case if you torque it to hard. You might want to try this using the
> > same cal procedure, and if it works go to the mount system.
> 
> except the bar has weight
> better to place it vertical and use a scale to get the weight required
> a 5" bar and 80 lbs pull would be 400 ft lbs
> 
> Clive

Not if he puts an Identical bar on the other side.  That is how we
calibrate load cells on dyno's in our test cells.  we have mounts on the
dyno and we have bars that fit into them on each side at centerline of
the shaft.  The two bars are equal length and weight so that they
counter each other and put you back to zero.  Than we add the weight. 
Our bars, since we have the room, are to put us four feet from center so
that we use 25lb weights to calibrate every 100ftlbs.  We have used this
method for years.

Matt