Will WI cause corrosion and pitting?

[cantona156]

Will WI cause corrosion and pitting on Cylinder wall n injectors?

Some material I found seem to indicate so ....
Any comments?

Thanks.
http://en.wikipedia.org/wiki/Water_injection_(engines)

[JohnA]

Originally Posted by cantona156

Will WI cause corrosion and pitting on Cylinder wall n injectors?

Not really :lol:
Water after all is a natural byproduct of combustion :wink:

And it's not like the whole engine is submerged in water all the time. For a tiny percentage of operating time a water mist is added to the airflow.
I've never heard of pitting on cylinder walls, that's a new one --- oh well...

[cantona156]

Oh heck, I am installing one soon anyhow. Likely Aquamist 2D.

Driving a Legacy with 2.5 STi block, running 1.5-1.7bar boost. My TMIC was totally overwhelmed.
Just installed a small FMIC. So the WI will come after my FMIC is settled (still leaking some air).

Anyway, based on my injector (650cc/min @80% duty cycle) & 10% water to fuel ratio, I am looking at 0.5-0.6mm nozzle.
I will be also be installing an Charge Air temp gauge, to see the effects with and without the WI (with 50% methanol).

The other thing is tuning. I was told we need to tune for leaner AFR 12.5:1 with WI ...to really see its effect.
Not very optimistic about this. But will try to convince my tuner to give it a shot.

[JohnA]

Originally Posted by cantona156

....Anyway, based on my injector (650cc/min @80% duty cycle) & 10% water to fuel ratio, I am looking at 0.5-0.6mm nozzle.
I will be also be installing an Charge Air temp gauge, to see the effects with and without the WI (with 50% methanol).

Keep us posted.
Don't expect a dramatic drop in charge air temps though, especially if the nozzle is placed *after* the intercooler. Heat exchange needs temp difference in order to be efficient.
Also mind the distance between the nozzle and the air temp sensor. If they are only a few inches apart there won't be much time for the mist to cool the charge down *and* register it on the sensor as well.

Most of the W.I. benefits come from in-cylinder cooling, remember, so a KNOCK sensor would show the difference of W.I. :wink:

The other thing is tuning. I was told we need to tune for leaner AFR 12.5:1 with WI ...to really see its effect.
Not very optimistic about this. But will try to convince my tuner to give it a shot.

If you're running 10 or 11:1 AFRs there is much less room for W.I. power gains. You can still push boost higher though.

[cantona156]

When I was on my TMIC, my charged air temp after IC was over 90degC after 2 runs.
Tuner had no choice but to richen the mixture. Currently doing 10.5-10.8, no thanks to the old TMIC.
The outside air temp was 32-33degC.

Hopefully with FMIC (quite a small one), I can see 50-60degC consistently ...
And let the 50:50 WI do the rest .... 40degC or so.

At 1.7bar, I am already running the limit of my autobox (52kgm). Can't run any more boost, unfortunately. :lol:
Hopefully, with WI like 2D (with real-time feedback), the tuner can run leaner a little, and run slightly more aggressive timing.
Of course, WI can provide some margin against poorer fuel in the future.

The other thing is, in event that I run out of water, clog injectors, pump failures etc, i can run lower boost, or even cut boost via my boost controller... as long as I am aware of the problem (via 2D hopefully).

[RICE RACING]

Originally Posted by cantona156

Will WI cause corrosion and pitting on Cylinder wall n injectors?

Some material I found seem to indicate so ....
Any comments?

Thanks.
http://en.wikipedia.org/wiki/Water_injection_(engines)

100% BULLSHIT

Had a look inside a motor that runs my WI and we have probably pumped though well over 100lt in testing and the engine is mint and so too is the compressor wheel

I love alot of these old wives tales circulated on the internet lol :lol:

[JohnA]

Originally Posted by RICE RACING

...I love alot of these old wives tales circulated on the internet lol :lol:

Old wives' tales :lol:
If they were true, we'd all be blind from the age of 12 :wink: