"Peter Dohm" wrote

The damper, which is indeed a relatively expensive part, is on the other
end of the engine and is intended to eliminate resonance within the
engine. A breif treatise, which probably started as an an internal
document at one of the big three auto makers, has been included on this
forum a number of times and is probably in an issue of Contact! Magazine
as well; but I can't find a copy on my current computer.

I could easily be incorrect about the purpose of the springs, but another
article from Contact! regarding the development of the BD-5 drive train
(which I also can not find) does provide some food for thought.

You are thinking of two different things.

The thing on the accessory end of the engine is the harmonic balancer, and
it does indeed dampen resonance in the crankshaft.

Dampeners also exist that go between the engine and the load, usually found
in industrial applications, or in marine applications.
--
Jim in NC