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Axle-hub dyno DIY

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Hi there, So we have landed in building our own Axle hub dyno Using the following components

4x KLAM CFK-500-ML Retarders

Sportdevices SP6 DAQ kit

Some sort of FANs.

I'm trying to finish up everything but i need a way to compensate for some degree of camber in my setup.

I was wondering if anyone has ever built on or have some other knowledge on how we can construct the adapter to allow for up to 6-8 degree of camber?

Also does anyone have any Cad drawings of generic wheel nut/lug PCD's for hub adapters?

I think your Retarder needs to be mounted so it can pivot to accommodate the desired camber. At least that's how Dynapack and Rototest do it.

The hub adapters used with Dynapack are 4 & 5 slotted devices that allow a range of bolt circle diameters with washers to slide in the slots. Since many of the cars I test use single-nut centerlock wheels, I've machined many adapters that have 4 or 5 studs that then bolt to the hub adapters.

The mechanism you use may need to be capable of allowing for camber change during the test, as it is normal for some suspension movement and hence camber change, especially with softer sprung and/or high torque.

Off hand, I would suggest using LOBRO type CV joints between the bolted on adaptor and the load device. They are available in a wide range of sizes and torque capacity, and from a wide range of suppliers. HOWEVER, there will also be a side load as well as the torque load, because the vehicle will be supported by them, and I don't know how they will react to that.

Most have the whole retarder move as David suggests. Mainline does it a bit different with some type of CV joint or other coupling so the flange moves but the retarder doesnt.

Have a look at Vic Dyno Hires you tube vid if you havent already, his uses airbags which I think is quite a neat implementation. https://www.youtube.com/watch?v=pwPP0Ex238M

Land & Sea have quite a simple design with just a spring loaded wheel at the back and the whole cabinet rocks up/down.

Also, take a look at Henning Larsen's facebook page, he has been working on one for a while and there are many detailed pictures.

i've looked at F4b - GT 50M flanged bearings as they are the bearings used by mainline. looks pretty stable but "expensive"

As for the adapters i'm not sure on how to calculate the different PCD's in cad for my manufacterer to build the parts.

The PCD is the easiest thing - it's the diameter of the circle the middle of the studs/bolts are fitted to. All you need to do is tell them the PCD, the number of bolts/studs the vehicle uses, and the diameter they need to be drilled to for the clearance.

What I would suggest, though, is that you check out your options with alignment rings - these will centre the hub over the axle's raised centre part, in the same way hub-centric wheel spacers work.

thx everyone i will take it to consideration :) We are also looking to use all 4 retarder to load one axle in the event we are getting a high powered Drag car.