the alumina insulator on the right plug is brand new! Dirty plug has ~1300miles, clean one has ~2200 miles.

 

I don't see

 

Both plugs are used:

- The one on the left has done 1300miles without WI
- The oner on the right has done 2200 with WI. Looks brand new?

Have I got it right?

Richard

 

Sorry for not being clear. That is right. The ceramic looks new! I shine a flashlight into the sparkplug hole, the top of the piston looks silvery, not the usual black.

 

Do you have a plug before water injection and when excessive fuel was injected as a coolant?

 

No..i tossed them...

The spark plug on the left i ran for 1300 miles w/o water injection at ~11 to 11.5AFR
https://www.evolutionm.net/forums/sh...4&postcount=49

The plug on the right, with WI, 2200miles with AFR not dipping below 12.5

 

slowcar, the picture brings up a point. There does not seem to be any "color" on the ground strap, my guess is it is washed too, so the old fashioned way of checking timing is no good with WI.
When you peer down inside, between the porcelin and the threads, do you see any color at the base?

 

No WI:
Ceramic near tip = gray
ceramic middle = white
ceramic down between metal/ceramic = black
metal surrounding ceramic = black

WI:
Ceramic near tip = white
ceramic middle = white
ceramic down between metal/ceramic = white
metal surrounding ceramic = black

what are you looking for

 

the old fashioned way of reading afr and timing was to check plugs. a little ring of color at the very base of the porcelain meant good afr. with timing you wanted darker color up to the bend of the ground strap.

as you can see that method of tuning is out the window with WI.

 

Water/alcohol is a good cleaner, especially at temps right before it combusts. I bet the unburned vapors will clean the O2 sensors and exhaust ports too.

I just had a thought as I wrote this: You think the exhaust is more dense, not only from temp, but vapors, providing more kinetic energy to spool the turbo?

 

I wondered that too.......like a steam engine...higher pressure cylinder, denser exhaust gas density to spool turbo......

 

Your engine's power output is limited by in-cylinder temperature and pressure . If you can operates at 2000degC EGT, you power will natually increase.

Water injection will allow you to push the incylinder pressure up but not temperature - the evaporated water expands to make extra pressure and at the same time reduces combustion temperature.

The WRC car has exploited that limit by runner and the engine's Compression ratio in excess of 10:1 and boost pressure of 4 bar absolute, lean afr and 98 ron fuel. Resulting in 600lbft of torque (with 34mm restrictor) Water injection is a vital part of the tuning program.

I wonder when this type of WI application will filter down to will the aftermarket tuning industry - I believe some of you are already going into this direction with WI. WRC car are not allow to run alcohol at all.

Further WRC tuning technology readings:
http://www.i-club.com/forums/showthr...ater+injection

Richard

 

What ambient temps are you running with these AFR ?? what ignition timing are you running up to 7000rpms ?? what intake air temps are you running??

Is there much difference between running 12.5AFR and 12.0 AFR ??

interesting thing is ambient here is lo to mid 90s and I get knock with approx 15% W-F ratio (usually at higher rpms) at 26psi..

Hmm.. think I'll upload a log on the parameters later .. on a separate thread later..

 

I know the gap decrease with alcohol, but do you need to decrease the gap even more as as the H2O% goes up and R-OH% goes down.?

I ran my 1.5 mi in 11.58
My Evo wont run 1.5 WOT until WI, 0.25 mi for now
I got a ride in a F-16 once back when I worked on that weapon, all I can say is you have one of the coolest jobs in the world, Sir.

 

I would only decrease gap if you are experiencing a misfire or p0300 code.

You want the largest gap able to be run without a miss.

The pistons also get a thorough steam cleaning! No carbon deposits will help deter preignition as there will be no hot ambers to light the impending fuel.