Broken small block Ford Scat crankshaft

[shady]

That's easy. Probably some dirt got into the mud valve throwing the discombobulator off balance. After that the megatransduty cycler couldn't re-balance it, creating some 24th order harmonics thus causing a perfect storm for failure. Either that or it just plain broke.

[pbf777]

    Yep!  Shyt happens!   

    But obviously this response just shows us that we're just not that smart; as without a cause, there wouldn't be an effect!   

   

An ATI balancer doesn't use any weights or fluids that can cause an off balance situation, such as a Fluidamper or Rattler design would.

    But, read the literature that accompanies the ATI unit, as is says: one can add, subtract or acquire different durometer value elastomer o-rings in order to "tune" the damper to the dampening requirements of your specific application.  What does that mean?  Well, I take it to mean: we make a great product, but we realize as a matter of fact that as shipped to you, it might not work, ideally, so we provide the opportunity inherent in the design and construction of our product to (perhaps) make it work properly! 

    And I applaud this fact shared statement, as an earnest admission that not any one piece of engineering is going to be proper, for any and all applications encountered.  The only problem is, how does one know if it's working properly or establish their specific requirements?  Are we looking at a hint in this failure presented?   

    Scott.

   

[cjshaker]

Interesting, Scott. I wasn't aware that ATI had different durometer O-rings available. And yes, figuring out which one works for a specific application would either require millions of dollars in research, or thousands of passes and examined failures and/or successes, but all would have to be based on a specific, and unchanging, combination. Personally, I don't think my bank account is big enough. 

[Katz427]

ATI had a couple of technicians, that went out in the "field" with equipment. Basically this consisted of an accelerometer, and a lap top with the necessary software. We ran the engine on the dyno, and the technician measured the crankshaft harmonics. About three of runs and he had it done , then another just as a check. I'm not sure what the cost was. They get fairly close just because they have so much data on various engine combinations, but, if you want or need a custom damper, they have that service.

[475fetoploader]

Does he stage the car against a 2-step rev-limiter? Say on the trans brake the car will stall at 5,500, but he stops it at 4,800 with a rev-limiter.

[RustyCrankshaft]

Interesting note on the Fluidampr's. I wonder what the issue with them is? On heavy duty stuff a fluid filled damper is the preferred option if available.

I have experienced the ATI durometer change, sort of by accident. Had to steal an oring out of another damper and that part number ATI I robbed turns out had a higher durometer oring that smoothed out the chevy I was working on. I know, but who reads that far down the instruction sheet? I gave up after the picture part.