DIY Shock Dynamometer, Feasable?

Hi guys.

(Skip to bottom for questions, read on for explanation)

For a while now I've wanted to make my own shock dyno so that I can start to revalve my own stuff and possibly for a couple of close friends. I also want to learn more about the effects of seal drag, nitro pressure, different shim stacks, etc. so that I can take the knowledge to college for Formula/Baja SAE.

I went around the net searching for designs that I liked, and settled on something similar to the Roehring models. It looked like a good design that could give repeatable results. I went through and designed the whole setup in Autodesk Inventor, making a few minor modifications along the way. None of the parts looked too out of my league in the fabrication aspect, so I'm feeling a little better about it.

Data acquisition shouldn't be a problem; I will be using a load cell to measure dampening force and a velocity transducer to measure the velocity of the shock at any given moment. At the end of the run I will overlay the data in a Force-Velocity graph.

I know that this design will produce a sinusoidal force wave. Is this a desirable trait?

I have attached some renderings of the rough product that I created in Inventor for you guys to see what I'm up to.

Now for the questions:

1) From reading some of Kevin Stillwell's posts, I've concluded that the maximum speed that I will need to test is around 70 ips. Is that true, or will I need to see higher values?

2) What kind of power will I need to have to turn these numbers if I ran the motor directly to the crank? I will put a gear system on the crank instead to gain a mechanical advantage and run a smaller motor, but what will I need?

3) What kind of force numbers will I get at a maximum? This will determine the size of the load cell that I purchase.

Thanks for reading,


Front Left.jpg

Left Rear V1.jpg

No Gears.jpg

Right Rear.jpg

Edited by baseballpro3112

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now