RE: PI

["Randall Young" <ryoung@navcomtech.com>]

> I can assure you that there is no correlation between rpm and fuel flow,
> there is a fixed end and a moving end to the fuel shuttle,

But isn't the motion of the shuttle itself derived from engine rpm ?  One
stroke per cylinder firing ? (Or perhaps it's 3 strokes per revolution, I'm
not clear on whether there is 1 shuttle or 6.)

> Also please bear in mind that the
> TR5 and Early TR6 (150) only makes 9.0" max

I'm guessing those are idle figures ... lower than the carb version because
of the more radical cam used in the PI engines.  But the exact vacuum makes
no difference to my argument ... the same thing applies even at 1" of
vacuum, the engine requires nearly twice as much fuel at 4000 rpm as it does
at 2000 rpm (for the same manifold pressure) *because* it's also drawing
nearly twice as much air and the fuel/air ratio must stay within a very
narrow band for the engine to run.

Randall