Thomas Borchert wrote in
:

That first part of your sentence is something I have NEVER heard of
before. Any source on that?

Anyone here work with water injection internal combustion engines? [Hey,
I round web sites which claim up to 60% more power, with no increase in
fuel flow. But I didn't rush out to give them my credit card number!
G]

And for the latter part: The excess fuel isn't doing any cooling per
se, it is slowing down the burning process, which leads to that
process being cooler.

Quite correct, but there is also a substantial heat of vaporization.

Also, 100 ROP is probably a bad point to be because it is the point of
maximum pressure load during the burning process. A little richer
(like 150) would be better.

True. But "better" is probably open to interpretation however. 100 ROP
gives best power, which also produces the highest peak pressure load -
exactly as you say. Is 150 ROP better? Well, the loads are less, and
so are the temperatures, but so is the power. Less efficient, wastes
more fuel, more pollutants in the exhaust.

A much better solution is to produce the same power but well LOP
(assuming your engine is balanced for it). The pressure wave integrates
to the same effective area under the curve, but the peak is not only
lower but less sharp in form. At the same time the fuel usage is at
maximum efficiency, and the exhaust is cleanest - not only from a
pollution standpoint, but also from the point of reducing any chance of
carbon monoxide risks.

Back to the first two points... anyone who tunes race engines for a
living or some such, want to weight in with more information. Wouldn't
be the first time I'm all wet. G

-----------------------------------------------
James M. Knox
TriSoft ph 512-385-0316
1109-A Shady Lane fax 512-366-4331
Austin, Tx 78721
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