SoCal shock dyno?

[Danglerb]

Installing a shock and driving around doesn't seem like a good way to test used shocks. Bilstein wants $25/shock to dyno, anyplace else in SoCal in the middle?

I've got 10 shocks I'd like to test, so I am tempted to build something like the $800 tester on ebay.

[mistertate]

Are they all the same shock, same valving? If they are and they're just some basic Bilsteins they're probably fine as long as they rebound and the pistons don't compress under they're own weight. Motons or JRZ would be a different story

[928 Bro]

if you cannot weld you can make the whole frame bolt on - not to hard. Interesting piece of equipment. Does it work by applying pressure or does it have some kind of bounce action?

[Danglerb]

Here is a link to a manual tester made from Unistrut (Home Depot adult tinker toys).

http://www.honda-tech.com/showthread.php?t=2325055

[MrGST]

Hmm...if you do build it, you could probably use this as a start point:
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=4711

[Danglerb]

All the shocks are Bilstein for a 928, but I have two that are early factory fronts, two early no idea factory or not rears, one almost new set of both front and rear, and two fronts a few years old. I did the simple compress and expand test with one of the middle aged fronts, seemed fine, put it on my 85 and it feels like nothing, almost no damping (more things to look at). Which brings me to wanting to test some other way.

How the first tester works.
Set a pressure of 20 psi with the regulator.
Open the air valve to the ram.
Record the time and pressure for a compression stroke.
More valve opening and closing for reverse stroke.
Record the time and pressure for a expansion stroke.
Step the pressure about +20 psi and repeat until about 100 psi.

Pressure to the ram is about force on the shock.
Time is velocity of the stroke inverted.
Plot the results.

****

The second one measures position from a pot in the hinge and force directly off a load cell, and you just wiggle the end of the beam to get different velocities etc.

[Danglerb]

Originally Posted by MrGST

Hmm...if you do build it, you could probably use this as a start point:
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=4711

I was thinking the same thing, PLUS should be possible to make it convertible between a 6 ton press and a shock tester.

[MrGST]

In case you want to start now, Harbor Freight is having a sale! Found this on RL:
http://www.harborfreight.com/cpi/emails/409/RetailU/409_retailU.html

[Danglerb]

Those coupons aren't supposed to be transferable, extra long bar code etc.

OTOH many I have seen print up the same all zeros at the end. I do have two of them addressed to me though.

I wonder if it might not be easier to modify a cherry picker, just swap the cylinder for a shock and put a measurey thing on it. I don't need to "measure" the shock either, just good/bad would be better than nothing.