inverse121: The DeskTop Dyno formula's do
not work in reality. Here's why:
1.The theoretical engine effciency is based
on 100%.
In reality this just does not pan out. Heat and friction losses that are "uneven" in the engine cycle, and impossible to measure, or calibrate instruments to read.
2.Problems and limits of combustion. The
"volumetric efficiency" of any engine
is never 100%.
Poor air flow, incomplete combustion, amount of intake overlap, and
atmospheric "pressure, density and conditions" all play into the formula. Out
here in the "real world" any engine will
never perform as well as one in a lab at
sea level and under exacting conditions.
Engine wear, state of tune and elevation all
play into this.
3.Mixture formulation, and the combustion
process.
The fuel your engine burns, is never stable. The octane rating as well as HC content varies from pump to pump. The condition of the engine's ignition system is never working at 100% level. As soon as you start and run the engine, the spark plugs
as well as the timing will vary and slowly
fade from "new parts and just timed state".
This applies no matter what kind of fuel
delivery system is used.
4. All the other variables that aid/deminish
complete combustion. Fuel delivery, uneven
fuel pump pressure, carb adjustments, fuel
injection pressure differentials and so on.
Air flow, into and out of, the head being the
single biggest issue here.(uneven, and not
balanced).
As with anything mechanical, any engine will
have heat and friction losses. Also the more
moving parts it has, the more complex the
problem becomes.
One cylinder will always lead (have more complete combustion) than all the others, hence it's trying to pull them along at it's pace and the others are trying to slow it down.
One rod/main bearing will always be tighter (more friction losses) than all the rest.
It's trying to slow them all down.
You get the picture...
Think Chevy! :rolleyes:
