[parmas]

Originally Posted by mrx79

Hi,

until now 350ccm Nozzle: W/F:60%@4000rpm -> 22%@8000rpm
new 140cc Nozzle: W/F:24%@4000rpm -> 9%@8000rpm

i decided to switch to a 140cc Nozzle.
Also switched from 100% Water (frist tests with the 350cc nozzle) to a WM50% by mass mixture.

Results so far (with tune basicaly untuched: AFR=0,8-0,85 / Advance: ~21-22?BTDC @ 16psi) DOES THIS AFR KEEPS THE SAME WITH OR WITHOUT WATER/INJECTION?

i experience a similar power loss with the 140cc nozzle as from the 350cc nozzle against the non-WI baseline run. ARE YOU USING A DYNO? IF YES POST DYNO RESULTS.

I then did some calculations on vapour pressure of water&methanol and checked this against my compressor efficiancy. This showes that my compressor is very effective and to keep the water/meth in steam form if once evaporated i have to run at least 18-19psi of boost to keep up the temperature with the rairing pressure after the turbo.
This also not includes the temperature drop from the evaporation.
PLEASE SHARE THESE CALCULATIONS

My calculations showed a too much amount of WM with the 350cc nozzle, so the power loss could be explained, but with the 140cc nozzle i'am in a good ballpark i guess and i'am also below 100% satuation so theoreticaly all the WM can evaporate if enough heat is present.

PLEASE SHARE YOUR CALCULATIONS

With this results i'am currently thinking if my setup is just too efficiant for pre-compressor injection - can that be the case?

That something is happening when activating WM is for sure, but what causes the power loss?! DUE TO SAME IGNITION TIMING VALUES

When i assume (just a guess) that most of the WM get's into the combustion chamber unevaporated it will evaporate there under the huge pressure and temps and reduces temps there by a "huge" amount.

YOUR GUESS IS RIGHT BUT DOESN'T MEAN THAT ALONE = MORE POWER

Methanol burn slower then gasoline. Water cools the combustion chamber. This would lead to the suggestion that i need more timing. But in fact, i'am still very uncompfortable with even higher amounts of timing.

WATER INJECTION IS NORMALLY IMPLEMENTED ON AFTERMARKET ECUs. WHY? BECAUSE THEY CAN HAVE FULL CONTROL OVER FUEL AND IGNITION TIMING. IF YOU ADD A MIXTURE YOU HAVE TO ACCOUNT THE ENGINE TUNE FOR IT NO MATTER IF IT IS STRAIGHT WATER OR METH. I CAN ASSURE YOU THAT WATER INJECTION ALONE WITHOUT TUNING THE BASE MAP IS A POWER KILLER

But this maybe can be a hint that at my current power levels, i just don't need WM injection?!?
By the way, i have to add: i'am running 98roz fuel and the basic compression ratio of my engine is 8.5:1, so fairly low.

YOUR COMPRESSION IS LOW, SO YOU HAVE A CLEAR RANGE TO PLAY WITH ON BOOST. DO A WIDE OPEN THROTTLE RUN AND SWITCH OVER EXACTLY AFTER. CHECK PLUGS AND IF IT IS BLACK YOU ARE EITHER RUNNING RICH OR IGNITION TIMING IS FAR TOO RETARDED. IF YOUR FUEL RATIO WHILE ON BOOST IS 0.85, THAN TIMING IS THE PROBLEM. IF YOU DECIDE TO INCREASE TIMING, FIRST ENRICH THE MIXTURE TO 0.75 THEN INCREASE TIMING ONLY THE LOADS WHERE WI IS TURNED ON. YOU MUST REALIZE THAT WHEN INCREASING TIMING ENGINE SHOULD RUN LEANER ALTHOUGH YOU INCREASED FUEL