I don't think Calculus understands knock...

Excluding catastrophic failure,
What I want to know is how is "c" determined
I mean say that you have a 10/1engine v1/v2 would be 1 to1/10 or 10; then

E%=100 x 1 -{1/10^c}

If I choose .5 for c, then E= 80%
If I choose 1 for c, then E=90%
If I choose 2 for c, then E=99%
If I choose 3 for c, then E=99.9%

But say you have a 8/1 engine,then v1/v2 would be 1 to 1/8= or 8; then

E% =100x 1-{1/8^c}
If I choose .5 for c, then E=75%
If I choose 1 for c, then E=87.5
if I choose 2 for c, then E= 98.44
If I choose 3 for c, then E=99.8%

So it seems like c would have to be less than 2 for sure,
and possibly less even than 1
but greater than 0

So what is"c"?