My new Water/meth results, with just the change of nozzle.

[Donkeypunch]

Hi,

I just got re-tuned the other day on my water injection system due to going to a bigger water jet. I was running the snow performance 175cc jet, and now am running the 325cc jet.

Here are the dyno plots on the 175 jet from a few months ago, on XXtuning's Dynapack.
This tune should be noted that it was really rich when we started on the baseline run without boost juice (alky/water). That was due to a injector dumping fuel when I got tuned with my VF-22. Once the injector was fixed the tune ended up being really rich since my tuner Tony had to add a lot of fuel because of it.
Anyway, the dyno plot below also shows the gain over the baseline without water/meth on a 175 nozzle. I also found out after that tune that my alky supply line was cracked and leaking during tuning. So we used less that optimum pressure for this tune.

175cc nozzle with cracked line tune, faint line is without water inject, darker line is with.



So here is the improvement with the 325 nozzle and nothing else added as far as bolt ons, only added a wastegate divorce pipe to my HKS downpipe.
(resized-Admin)



Here is AFR/Boost
(resized-Admin)


Granted we used very high boost for this tune on the dyno, and did road tune after with the boost turned down a little, because I wanted to feel what it was like. Man was it fast. So I am now back to running 20 lbs of boost in 3rd, and about 21-22 in fourth, and maybe around 23 in fifth. But I am not doing this for sustained periods.
Even with the boost turned back down to where I was running it previous, the car is still why quicker than before with teh 175 nozzle. The torque is friggin amazing. 1st through 3rd pulls are exilerating. The tune is way more aggressive but still safe with lower boost. The car never knocked during the dyno tune, and only knocked once during the road tune when rolling into the throttle after being in vacumm for a while. I am being careful though how hard I push the motor and tranny.

Here are the mods.

2004 WRX
Stock 2.0L internal wise
HKS downpipe
VF-22 turbo, not ported or clipped
TurboXS uppipe
Ceramic coated stock header
UTEC
Perrin Short ram
MRT TMIC
Snow Performance stg. 2 Boost cooler water injection system using 325 nozzle. ( I am thinking of the pump upgrade also, I want more injection pressure), Running a 50/50 mix methanol/distilled water, or Denatured alky/water
Stromung Cat back twin tip. Exhaust has no cats what so ever.
Walbro 255 fuel pump
PE-650 injectors
I also have all the pre-requisite suspension and brake mods done also, so the car is ready for the speed, so is the driver.
After my first tune with water injection I was a big believer in water injection, and now even more happy with it. At one point in the torque curve I picked up about 100 ft lbs, around 3250 rpms. At peak torque I gained almost 50 ft lbs, and close to 25 HP.

Disclaimer:
I am by no means condoning running sustained boost of 25+ lbs through a stock 2.0L block, and am not saying my set-up is the best. I just posted this for information, and to show the benefits of water injection, for those interested or just not sure if it is for them. I was very skeptical when I started reading about this stuff around a year ago, but am now really happy I went down this route. So lets not turn this into a flame war or what not and get carried away the way some threads do with peoples opinions. If you have questions I am more than willing to answer to the best of my ability.

I believe it has allowed me to get what I wanted out of my tune with a little more comfort than running just pump gas.

DP

[JohnA]

Midrange you were hitting 25psi with 12:1 AFR eh?
No wonder it was pulling hard!

Interesting graphs, thanks for sharing

[Richard L]

Excellent post, thank you. I was wondering if you have planned any failsafe attachment to your setup. Running 12.5:1 is good for race fuel but it is quite brave for pump fuel, some tuners will cringe even with WI.

I believe Snow offers a flow switch that detects low flow called "safe-jection" May be you can consider using it.

Thank you for sharing.

Richard

[Donkeypunch]

Richard,

I am looking into that, and I have to get low level switch soon also. I am really good at checking my resivior, I check it everytime I get out of the car almost, but I am going to get one. That 12:1 AFR seems to work the best on the Imprezas, and it didn't knock once. I am not running that much boost on the road though. Only 22 lbs max on the road, but still pulls way harder than before.

DP

[AndrewC]

I may have missed something, but surely they aren't flywheel figures?

I would have expected a VF22 without WI to make more than that at 20psi never mind 25?

Andrew...

[Spudster]

Originally Posted by AndrewC

I may have missed something, but surely they aren't flywheel figures?

I would have expected a VF22 without WI to make more than that at 20psi never mind 25?

Andrew...

Looks like a misnomer... should be whp. The boost axis says absolute pressure when it's actually relative. I guess some dynos don't sweat over such details.

-Steve.

[Donkeypunch]

They are WHP, the pull down menus on the chart that were selectable on the dyno monitor, say Torque and Horsepower, Flywheel corrected. THe correction is computed as at the wheels.

DP