water injection

[Greg Hermann]

 Cylinder temperatures are
>> around 2000 F so any water that's in there goes out with the exhaust.
>>

More like high 4000's to low 5000's (F.) peak (burning gasoline), depending
on compression ratio and efficiency of intercooler.

>Anywhere the water exists as water, and not "dry steam" corrosion is a
>distinct possibility. Particularly in the "injectors"
>Get a bit of water into the fuel on an EFI engine and let it sit a
>couple of weeks - then try to figure out why it runs like doggy-doo.
>Been there, done that - got the T Shirt.

True enough, if it is an open system. But the real culprit is oxygen
dissolved in the water. "De-aerated" water is not particularly corrosive.
Wet steam is ABRASIVE as anything, not really corrosive--about like
sand-blasting--this is why a head gasket leak will clean a chamber. And why
letting the steam in a steam turbine go wet will wipe out the turbine
blades in a HUGE hurry.
>
>> > Water injection is just a reason for doing a poor
>> > job, if you want an engine to give 600 bhp and there is a chance you may
>> > blow it because it is being pushed to the limit, do not build it.
>>
>I would tend to agree. Proper design will not require water injection -
>and water injection will not fix poor design - just mask the symptoms.

I disagree here. I think there is a lot of unexplored potential for
improvement with sophisticated water injection. For instance--what might
happen with DIRECT (straight into the chamber, after the intake valve has
closed) water injection? Some very interesting (buckets of caffeine, and
several Excedrin) thermodynamica involved if one tried it this way!!!

Regards, Greg