Earl Wrote:
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> The reason 493 has a mushier exhaust is that 482
> is doing most of the work. 493 is not working
> hard at all and the engines are not sharing the
> load equally.
>
> 480's and 490's have the same cyclone front end
> setup, and the same size cylinders, so they sound
> pretty much the same doing the same amount of
> work, taking in such variations such as valve
> timing, Johnson Bar and throttle positions,
> weather, condition of valve and piston rings, etc.
> Tight rings have a lot to do with how snappy and
> engine's exhaust sounds. An engine with worn
> rings will be less sharp but actually louder as
> live steam gets past the rings and goes up the
> stack.
>
> 480's and 490's really don't sound off until you
> load them down to 50% capacity.
>
> Comparing modern audio recordings to 1960's
> recordings tells you nothing as you have no idea
> what kind of equipment was used, with different
> frequency response, etc.
>
> When 493 was converted to oil firing the same
> exhaust nozzle was used. The petticoat pipe was
> extended down further, replacing the cyclone
> assembly. To me, 493 sounds pretty much like any
> other freshly shopped 480-490.
>
> The 470's have Master Mechanic front ends with
> higher exhaust nozzles. Simply pulling baffles
> and floor plate out, and leaving the nozzle and
> petticoat pipe in place would probably work pretty
> well. The result would sound pretty much like it
> did before.
>
> It does seem the 473 has taken quite well to its
> oil conversion.
Thanks Earl, appreciate your comments and insight. Makes a lot of sense.
William
aka drgwk37
