Pre Turbo Water Injection

[jet_r31]

It will just pool in the intercooler won't it? I would be spraying at high pressure (at least 200psi) preferably after the BOV.

no way, its hasn't been a liquid for a long time, before it gets anywhere near there , i have run it for along time as has my brother, and his freinds now

all pre-turbo, all 25psi+ 98 octane tunes

pre-turbo is best for WI, just have to get around the compressor wear bit

cheers

darren

[sucram]

The nozzles for pre turbo are devilsown nozzles. They are not a "jet" but a mist. It is their DO.75 which they rate at about 50cc.

Measuring them with the pump im using results in a little more then what they rated them at. It was tested with water only, water/meth

flows a bit faster but I doubt much difference with such small nozzles

Testing them off the car results in the majority of it evaporating after about 80cm. This indicated that there probably wont be enough flow

and that the droplets are fairly small. Add to that im running a 50/50 mix by weight which is approx 40/60 water/meth volume which is

probably way too much meth for pre turbo since the meth will flash so quickly

The pump im using should be well over 300psi, I couldnt test it with these nozzles since I couldnt find my pressure gauge. Its running a

2 port solenoid mainly for shut off to stop drips and siphoning. Nozzles are mounted in the top of the filters

[jjman]

nah im not a hater. I think it is an awesome idea in theory n more stuff like this should get done.

The problem is, n hence all the contrary comments, is that he is doing this to stock turbos on what sounds like a good motor (hence getting ready to put some 2530's on it).

But due to the known reliability issues with stock GTR turbos and the catastrophic consequences of failure, it seems very reckless to be not only using them un-neccesarily but also doing something to them that is increasingly likely to make them fail.

This sort of experiment on his fresh 2530's id be cheering for. But like this just seems silly as he could kill a perfectly good motor...

[sucram]

Continued. Ran out of time before...

I dont intend to replace my post IC set up with pre turbo only. That was never the intention. Injecting to the point of being able to tune off it would result in nothing but testing the advantages of both. Im trying to isolate the pre turbo side of things since I already know what injecting post IC does.

I considered the air atomizing nozzles but its not for me, maybe later. Basically they are a derivitive of a spray gun nozzle. Introducing a leak into the system seems probmatic.

Im far from being a self proclaimed water injection expert, but this isnt my first gig. I am playing with pre turbo WI to answer my own questions and curiosity and as expected, some questions are being answered while it opens up new questions.

If I find bonafide results from 3rd gear logs I might take it to a dyno. While I dont get free dyno use anymore, its practially free but for me its far more convienient to do 3rd gear logs and compare speed Vs. time and break them into sectors to see low, mid or upper gains if any

At the moment, im knock limited. The only way to move forward is testing larger nozzles which I will have to order. Probably will have to go to the point of injecting till the engine noise quietens and go down 1 or 2 sizes or just go off the heat the greddy pipes are generating after a run. This is probably the only way to roughly figure out that there is being enough water injected but not so much its going through the IC and into the engine without buying thermistors.

I guess in the mean time I can test it with the boost control off which is about 10psi with the system off and then switch it back on for back to back

As for maxing out the stock compressors, I have my doubts. There was a guy in the US who was rebuilding his engine and ran them up till they blew, started at 14psi and got to 450hp and 25psi till his particular ones let go. Im game but not stupid.

[sucram]

The problem is, n hence all the contrary comments, is that he is doing this to stock turbos on what sounds like a good motor (hence getting ready to put some 2530's on it).

But due to the known reliability issues with stock GTR turbos and the catastrophic consequences of failure, it seems very reckless to be not only using them un-neccesarily but also doing something to them that is increasingly likely to make them fail.

This sort of experiment on his fresh 2530's id be cheering for. But like this just seems silly as he could kill a perfectly good motor...

The 2530s are off for mods, they wont be rebuilt, just modified.

since compressor errosion is a very likely I thought testing this stuff while its off is as good as its going to get. You cant get the HKS comp wheels like the garretts

so risking it isnt feasible. If I had -5's it might be a different ball game since comp wheels are $110 each.

I wouldnt worry about the stockers too much. This set was originally on the car, ran atleast 1.2 bar for 5 years straight. Had a stint at 18psi which would spike 19.5 in the upper rpms.

Even previously on a stock ecu and stock boost control it would hold 15.7psi above 6500rpm and it ran that way for a year or so.

[jjman]

The 2530s are off for mods, they wont be rebuilt, just modified.

since compressor errosion is a very likely I thought testing this stuff while its off is as good as its going to get. You cant get the HKS comp wheels like the garretts

so risking it isnt feasible. If I had -5's it might be a different ball game since comp wheels are $110 each.

I wouldnt worry about the stockers too much. This set was originally on the car, ran atleast 1.2 bar for 5 years straight. Had a stint at 18psi which would spike 19.5 in the upper rpms.

Even previously on a stock ecu and stock boost control it would hold 15.7psi above 6500rpm and it ran that way for a year or so.

fair enough. But when that day comes....

[jet_r31]

Out of interest , if your knock limited atm, have you tried just straight water

cheers

darren

[crack]

[sucram]

water is an option I want to test, I also grabbed my jet drills so I can drill the nozzles if the need be. I wanted to do this over the weekend but ran out of time.

That link above is a guy who tested various nozzles

http://www.dsmtuners...st-results.html

Set-up specifics: The engine on the dyno was a relatively stock 2.3L Ford engine out of a late 80's Thunderbird. The turbo was a Holset HX-35 running at 22-23 psi. The engine was producing roughly 450HP and 389 ft/lb torque. The nozzles were all mounted in the same location throughout the tests - about 4" away from the compressor nut. The pump used was the Devil's Own 250 psi pump.

Here are the results that we gathered:

No injection;

Before IC temp increase - 29 deg/sec

After IC temp increase - 4 deg/sec

Peak boost 22.09 PSI

------------------------------------------------------

1GPH 50/50 mix;

Before IC temp increase - 19.1 deg/sec

After IC temp increase - 3.0 deg/sec

Peak boost 22.88 PSI

1GPH H20;

Before ic temp increase - 24.2 deg/sec

After IC temp increase - 3.4 deg/sec

Peak boost 23.21 PSI

1GPH Washer Solvent;

Before IC temp increase - 24 deg/sec

After IC temp increase - 3 deg/sec

Peak boost 22.96 PSI

---------------------------------------------------

7GPH 50/50 mix;

Before IC temp increase - 16.9 deg/sec

After IC temp increase - 4.5 deg/sec

Peak boost 22.96 PSI

7GPH Water;

Before IC temp increase - 13 deg/sec

After IC temp increase - 4.7 deg/sec <---no IC fan - OOPS!

Peak boost 22.92 PSI

7GPH Methanol;

Before IC temp increase - 19.3 deg/sec

After IC temp increase - 3.5 deg/sec

Peak boost 23.0 PSI

7GPH Washer Solvent;

Before IC temp increase - 11 deg/sec

After IC temp increase - 3.8 deg/sec

Peak boost 23.3 PSI

-----------------------------------------------------------

10GPH Methanol;

Before IC temp increase - 14.3 deg/sec

After IC temp increase - 3.2 deg/sec

Peak boost 23.05 PSI

10GPH Washer Solvent

Before IC temp increase - 11.2 deg/sec

After IC temp increase - 3.4 deg/sec

Peak boost 22.71 PSI

I think he mentions why they were getting surge at the end of the run in the above link.

I have tested pre ic and post ic on a car a while ago. With the right size nozzles and pump you can basically do away with your IC. Problem is you need atleast a 15ltr tank and you need

to spray pretty early to get any form of consistency otherwise the heat compounds. When you pump enough pre ic (I would imagine pre turbo too) you loose IC efficiency, so it basically

starts to heat the air. Running another nozzle before the throttle body recifies this

So, if I start injecting too much I start to go backwards. It would make sense to find the point just before this happens to isolate how effective pre turbo injection is. Then intergrate the normal

water injection back in to combat any negligable negative effects of "interheating" and to do what WI normally purpose. There are guys who spray so much into the turbo that they see benifits

at the engine, but in my experience its best to be able to manage the amount going into the engine without having to do a shit load of testing finding out how much the turbo is consuming,

how much the IC is consuming (and this can be VERY inconsistent) then hoping you get enough at the ports.

I digress, next logical thing to do is test water only, I would bet my left nut that the majority of the meth is being evaporated before it gets to the turbo, good for cooler intake temps

but not so good since I suspect the current nozzles are too small to be effective. Then drill out the nozzles and retest water and water/meth. To give an idea of the nozzles, the smallest

jet drill I have is 0.3mm and it wont fit in the orifice! There is also a "pill" insert inside the nozzle which directs flow and can also limit flow. Without it the nozzle wont fog and shoots a Jet

of water.

Here is a pic I found on the net of a typical nozzle insert

These slots are much larger then the DO.75 nozzles which also have only 2 slots, maybe the thickness of paper! So while drilling the nozzle orifice larger, in

reality I will probably need to figure out how I can make the 2 slots in the DO.75 nozzles either wider or deeper or maybe even both?!

Any ideas?

Edited September 5, 2011 by sucram

[jet_r31]

Interesting, i spray 700ml per minute for around 680-710hp on 26psi on at the crank in my old motor on 98 octane , On ausrotary one of the guys was spraying 1500ml i think per minute on a 13B turbo with a GT42 and 35ish psi on 98 octane

I thought that the only thing stopping you really adding more water was generally the ignition side of things as its hard to light so much water.

cheers

darren