DIY hub dyno on the cheap

[BennVenn]

This is probably the only 'critical' part of the build. I'll design up the above style hub joiners and send them off for a quote. They will likely end up at around $80 a piece which is still in the budget and i'll know it won't shake itself or my car to pieces.

[immortality]

It may pay to also have those trailer hubs spun up and checked to make sure they are true. Also, they aren't hub-centric so it may pay to have rotors and hubs machined as a pair with a shoulder to make it easier to assemble and make sure it runs true after it's taken apart and put back together etc.

[BennVenn]

One more reason to use commodore or AU falcon hubs as a starting point.

I can chuck these up in the lathe and put a shoulder on them so it's not a huge problem.

[BennVenn]

A little more searching and the real hub couplers aren't hub-centric. Maybe it's not that big an issue.

[delcowizzid]

Thus is how the dyna pack setup works could do the same and slide onto a cv shaft

[Gampy]

Any competent machinist would be able to index two rotors together turning them into a flange adapter ... That would be sweet, to dyno a different bolt pattern you just need a rotor to match, that is indexed and bolt patterned to your drive rotor.

As well as truing up and indexing everything.
I'm sure if you wanted to spend the bux there is someone that would also balance it all, a waste IMO, good machining should get balance good enough.

Rotors are hard and cast, I'd be a bit concerned of fracturing ...

PLEASE do us all favor, build a scatter shield over these rotating parts so there are no unfortunate shrapnel accidents if something does happen to go wrong!

How about yard sale leaf blowers ... I see electric leaf blowers real cheap (couple bucks) all the time because of a cracked strain relief on the power cord and people get scared they are going to get shocked!

[BennVenn]

I was planning to have a steel tray / band around the disc to catch the cooling water so i'll beef that up and it *could* double as a scatter shield.

A bit of a sanity check though, the 14" wheels on my pulsar would be spinning at 1000rpm at 110kph. Doing the numbers, there's about 1.5 times the energy in that rotor than a .22 round (though if it did fragment, each piece would have a fraction of that energy...) and it has 1.2tonnes trying to pull it apart. A scatter shield is definitely needed. I was well clear of the rotor on the engine dyno and knowing that it survived at 5000rpm under significant loads gives confidence of their strength.

Given the simplicity of a rotor to rotor I think I'll give that a go. I'll use new rotors and have them machined by a professional. I think the risk could be mitigated with the scatter shield and using off the shelf rotors means it'll be very easy to support different hubs plus they'll be hub-centric. The only problem if it did fail is the car would drop to the ground.

If this does work, I'll eventually get cnc hubs made up. They will likely be the same price as 2 sets of rotors and machining anyway

[BennVenn]

Thus is how the dyna pack setup works could do the same and slide onto a cv shaft

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CV shaft annealing and heat treating is probably beyond my skill level. I did it for the engine dyno and even with a couple hrs of dull red heat in the shaft, it ate up a carbide bit when turning them. If i can avoid shafts and splines, it'll make it much easier i think

[BennVenn]

Out of curiosity...

I sent this off for a quote on 4 pcs - 114.3PCD and 120PCD for ford and holden hubs.

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Might just blow the budget...

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[Tre-Cool]

I'm building my own hub dyno "on the cheap" too.. but as i'm building it to tune up to 3000hp. im using a couple of Klam CFK-500's (rated to 3820ft lb each) about 10k each. then bought the sports dyno sp5 kit.

i just don't see the value in the minimum 95k kits from mainline or Dyno dynamics.

A friend's got a drafty on his payrol so it's all been done in cad & his guys will build it once done. Helps to have friends who are also rev-heads so we sort out costs between us.