Inexpensive shocks dyno'd...

[Jenson May]

Originally Posted by OrbitalEllipses

KW is very evasive about their dynos. I don't think any end-user who has asked KW for a shock dyno has received one. That was last I heard a few years ago, things may have changed now.

I will try and find a dyno when I get the chance of a KW V1
From what I remember it was very similar to a Koni yellow

[Jenson May]

Per requested I had the chance to dyno a BRZ / FT86 shock after work.

Here is a PVP graph of a front shock (500 series). The red line represents jet open or full soft and the green line represents jet closed or full hard. The PVP graph is what most manufacturers use when publishing dynos. It basically takes a reading of a damper and samples it at various inches per second. Our test is setup to take readings every inch per second (1ips - 9ips) This is pretty much the industry standard:



The next graph is also a PVP graph with the same sampling methods. However it covers the whole sweep adjustment range of the damper. I conducted the test in 2 click increments roughly. I also want to note that this test started at 85 degrees and ended at 103 degrees. When conducting a PVP test it takes roughly 45-60 seconds to test the damper at each click level. Samples are taken at each inch per second and the shock temperature will begin to rise. I had to run the dyno 14 times (roughly 45 seconds each time) So it heats the shock up considerably. What does this mean? I technically should have waited for the shock to cool down after each test, however I wanted to get home at a reasonable time so I just dynoed them back to back.

When the damper increases in temperature the force readouts will be bit less. For example if I test a shock at 85 degrees and it reads 200lbs of rebound force, at 100 degrees it might read 195lbs of force. So the results are every so slightly skewed but I think this will be fine for what we are doing.

You can also see that there is a slight amount of cross talk on the compression side. In my opinion this is really not that big of a deal since its just a matter of a few lbs of force. A very good driver would not really be able to tell the difference at these levels.

You will also notice that the force is not equal at each click and more force adjustments are seen at stiffer levels (jet closed) This is pretty common on needle style jets and separates the mega dollar shocks from the not so mega dollar ones

Is this good enough for a ALMS team? No definitely not, but a ALMS team would not be using single adjustable shocks in the first place. Is this fine for a HPDE weekend warrior? In my opinion this is more than sufficient.



I also have a CVP non averaged graph of the damper set to full stiff (jet closed) This helps show if there is any excessive hysteresis in the damper. In our case there isn't anything to write home about and the hysteresis levels are very acceptable.



Lastly I conducted a CVP football sweep plot. We normally do not really use this graph, however since one was previously posted I will go ahead and post this one up. This test started at 97 degrees and ended at 94 degrees. A CVP test is very short (2-3 seconds) so the damper actually cooled down on the dyno when I conducted the sweep test.




If anyone has any questions please let me know. Or if anyone has a shock absorber that they want me to dyno, so that we can post up in this thread. Just PM me and I can do it. I request that you only send me 1 shock without any ancillary parts such as springs, mounts and top hats. This makes it easier for me to dyno the shock. I will not dyno all 4 of your shocks as that will take me a few hours

[Xdragonxb0i]

So what's the skinny on FA 500? How would these compare to ground control street basis?

[Captain Snooze]

@Jenson May. If you were able to I think it would be interesting to see the results of testing an inexpensive damper that features a gazillion "adjustment" clicks.

[fooddude]

Bump for any more added info - lot's of great info here

Also...more info on the 510.