Tuning W/I via Humidity Sensors

[rotrex]

ww2 engineers did the tests up to 1.5:1 water to fuel.
The slope went always one way. more boost + more water = more power.
So there is plenty of headroom from your 350cc jet :-)
What engine is it? A 1FZ-NE? Forged pistons?
Cast pistons are more often than not the first thing to go sauer.
I still suggest to install charge cooling. It combines well with water injection.

I have seen intake air temps drop 10-20C max using water injection. More with adding methanol, even more doing precompressor injection.
Doing direct port injection, there is barely any IAT reduction, but I can still benefit to a similar degree, if not even more. I have no dyno, so can't tell you in terms of % power/torque.
A 10-20C drop is rather little compared to what a charge cooler does. Even a small one will reduce IATs by 30 C or more. The decent ones get you to 10C above ambiernt, so in your case about 80-100C reduction in IAT.
That is why I suggest let a charge cooler do the charge cooling and the water injection do the in-cylinder work. They both add to the performance potential.

if your current tune is already at best torque, so not knock limited, you only can up the boost to get more flow/power in its current configuration.
If your engines knocks before hitting best torque upon further ignition advance, add more water/methanol and try again.
Where the limits of your engine build are, you need to do your own research or blow an engine.
As you run no charge cooler, you may try precompressor injection.

Regarding AFR, I have found that such a "lean tune" provides good power, but generates considerable heat. I have only observed this on track. 12:1 yielded about 85C coolant temp and the 13:1 about 90C on that particular day. Both were with w/m injection. Nice thing was fuel consumption was significantly lower in that session.
On the road doing short burst of WOT, it probalby won't matter. temp wise

My cylinder air distribution is not that uniform with Nr.1 running a tad leaner. The plenum is not designed for forced induction. The plenum chsmber has a side entry and a uniform cross section along the width. This leads to more airflow at ther first cylinder and less towards the other end.
Running the engine at 12:1 keeps them all somewhere around this number. It lowers overall combustion temps and cylinder head and valve temps with it. In your case also turbo temperatures.
Riceracer propagates 11.8:1. This is rich best torque. It adds safety and costs barely any power vs. a leaner all out tune.

[parmas]

Originally Posted by rotrex

ww2 engineers did the tests up to 1.5:1 water to fuel.
The slope went always one way. more boost + more water = more power.

I AM SURE I DID READ IT SOMEWHERE

What engine is it? A 1FZ-NE? Forged pistons?

ACTUALLY 1NZFE - ARIAS FORGED 8.5:1 Compression. Although block is open deck and cylhead is completely stock


I still suggest to install charge cooling. It combines well with water injection.

Actually I do like the simplicity of my setup. Charge cooling is not considered for now. I also like faster spool up time

I have seen intake air temps drop 10-20C max using water injection. More with adding methanol, even more doing precompressor injection.
Doing direct port injection, there is barely any IAT reduction, but I can still benefit to a similar degree, if not even more. I have no dyno, so can't tell you in terms of % power/torque.
A 10-20C drop is rather little compared to what a charge cooler does. Even a small one will reduce IATs by 30 C or more. The decent ones get you to 10C above ambiernt, so in your case about 80-100C reduction in IAT.
That is why I suggest let a charge cooler do the charge cooling and the water injection do the in-cylinder work. They both add to the performance potential.

I use the car mainly for street. Going slow and off boost will net about 35C-40C with an ambient temp of 25C. Injecting water @ 2psi and full injection @ 10psi will not let IAT to go over 35C @ 18psi. After full throttle is closed, temps go below ambient to 15C-20C for several minutes.

if your current tune is already at best torque, so not knock limited, you only can up the boost to get more flow/power in its current configuration.
If your engines knocks before hitting best torque upon further ignition advance, add more water/methanol and try again.
Where the limits of your engine build are, you need to do your own research or blow an engine.
As you run no charge cooler, you may try precompressor injection.

PRE-compressor injection is going to be used within the next weeks beginning with 150cc and leaving 350cc post turbo. I never heard knock till now and ignition advance is about 30Deg @ 6500Rpm 18psi. Again since engine block is not sleeved and cylhead is bone stock, it is likely to be boost limited

Regarding AFR, I have found that such a "lean tune" provides good power, but generates considerable heat. I have only observed this on track. 12:1 yielded about 85C coolant temp and the 13:1 about 90C on that particular day. Both were with w/m injection. Nice thing was fuel consumption was significantly lower in that session.
On the road doing short burst of WOT, it probalby won't matter. temp wise

At 12.5AFR the plug shows considerable amount of soot that it could be leaner. At 13.5 AFR seemed best. At low boost 0-4psi is also 14AFRs. The only difference I saw is in EGT temps. At 12.5, I was 650DegC while @ 13.5AFR above 710DegC

My cylinder air distribution is not that uniform with Nr.1 running a tad leaner. The plenum is not designed for forced induction. The plenum chsmber has a side entry and a uniform cross section along the width. This leads to more airflow at ther first cylinder and less towards the other end.
Running the engine at 12:1 keeps them all somewhere around this number. It lowers overall combustion temps and cylinder head and valve temps with it. In your case also turbo temperatures.
Riceracer propagates 11.8:1. This is rich best torque. It adds safety and costs barely any power vs. a leaner all out tune.

Mine is rich on cylinder one since it is the last cylinder on the side distributed plenum. The strange thing is that all the other three are well balanced. I actually do cylinder trimming on that one and reduced fuel actually.

....... Alex