I see that the AFR at high revs hovers around 11:1

Have you tried to go leaner? I got most of the gains when being leaner than 12:1, all other factors being the same.

Also is it running race fuel? If so, the gains from these four nozzles might be more modest, especially if the FMIC is really good.

What sort of charge temps does it register after a few seconds at full boost?

At the time of the test, we have no information of the actual WI percentage to fuel so we were a bit careful until we have calculated the correct afr.

Knowing the sto for methanol is 6.6:1 and gasoline 14.7:1, the correct a/f ratio of the mix has to reflex the mix, is that correct?

We will resume the test as soon as time permitting. This time we will plan it first compared to tuning the engine for race in 12 hours ahead. The next test will all the temperature sensors installed and logged. At preset I have a few big projects to complete.

The entire test was run on pump fuel - race fuel was not permitted on the race.

True, but at 50% methanol the Water/Fuel ratio has to be over 20% for the shift in the stoich point to become an issue, right?
Also the more the alcohol percentage, the less the atomisation deficiencies of petrol, and the cooler the burn, so one can go even closer to stoich at full boost.
Pump fuel, nice, so we can see some of the 'octane boost' effects in action! :D

When time permitting, I will get a set of logged data published here so you can see the effect.

Please don't treat the published power output is the final result - there are lots and lots of testing, furling and timing optimisation to be done yet.

I was merely show the dramatic effect on the a/f ratio with just water alone - still puzzled.

I am hoping to see a lot more gain form now on - since we have the use of a dyno and a twin pump aquamist system. Almost unlimited supply of methanol, nitromethane etc - just needs to find time.

Watch this space.

I getting to like this picture a lot.

Nothing to report yet.

[quote="Richard L"][quote="JohnA"]I see that the AFR at high revs hovers around 11:1

Have you tried to go leaner? I got most of the gains when being leaner than 12:1, all other factors being the same.

Richard,

Of course it will vary the amount of fuel and water being injected, but on my personal car toggling the WI on and off results in about a 0.04 increase in lambda (~0.6 A/F), and I'm running nowhere near 20% water/fuel.

WI appears to have a significant impact on lambda readings. I mention this only to point out that the Skyline may not be running as rich as it may first appear.

It would be interesting if you could perform a similar test to gather some data on the WI/ effect on lambda readings for comparison.

Mike

[quote="Richard L"][quote="JohnA"]I see that the AFR at high revs hovers around 11:1

Have you tried to go leaner? I got most of the gains when being leaner than 12:1, all other factors being the same.]

Of course it will vary the amount of fuel and water being injected, but on my personal car toggling the WI on and off results in about a 0.04 increase in lambda (~0.6 A/F), and I'm running nowhere near 20% water/fuel.

WI appears to have a significant impact on lambda readings. I mention this only to point out that the Skyline may not be running as rich as it may first appear.

It would be interesting if you could perform a similar test to gather some data on the WI/ effect on lambda readings for comparison.

Mike
espritGT3

this is a superb topic with excellent info.I have some questions.Firstly i will introduce myself.
I have been running a 1550hp nitrous 600ci V8 in a class called Street Eliminator.Best time and speed in the 1/4 was 8.2 at 177mph in a 3000lb street legal car.Bearing in mind we have to use Optimax(with a commercial booster) and block treaded tyres. We have used the ERL system on the car but found after a while we didn't need it with the nitrous as detonation wasn't a problem(even with 600+ nitrous injected in 2 stages). I am now putting on 2 x 88mm turbos on a 572ci V8 that has to be run in the same class. We will be shooting for 2000+hp on Optimax and tetraboost. I am also going to use an air to air cooler because of events like the king of europe which has a 20min turn around and it would be impossible to use ice water in an air to water system. I will be removing the port WI system and moving the nozzles around.i also have a plate under the throttle body with 4 nozzles in that i will keep.these are .8mm. the nozzle system uses .4mm x 8.I will also inject a couple of .4 nozzles after the intercooler.Now,the pre turbo injection seems like a fine idea but what nozzle size would i need,and how many? How far away from the compressor are you injecting from? straight shot at it or against the tube wall?Also has anyone injected WI just inside the intake pressure port of the turbo? I know from previous experience that a 50/50 mix of water/methanol works great injecting with an rpm switch,and a sureflo pump and solenoid(which i still have). Also bear in mind that the water injection system would only be on for about 10seconds max in the burnout and low 8 to high 7 sec in the run.
Your input and info would be highly appreciated on this one.
BTW,a piccy of one of the turbos for the install...and yes,Holset have sized the turbo for the application,and are giving me their valuable input...
ANDY FROST.
http://pic.piczo.com/img/i32663166_31036_2.jpg
PS,could someone post a pic of a pre turbo nozzle placement?

Visit us at www.redvictor1racing.co.uk

Injecting straight into the 'eye' of the compressor is not a bad way to go.

PS
that's a small mug you've got there (or is it a big turbo? hard to tell, lol...)

thanks for the reply John.Now if i'd have looked at the rest of the topic before i'd posted i could have got most of my answers...
Did Richard ever get those centre jet aluminium castings done?
The thing is that injecting into the centre of the turbo on this application would be quite difficult without something of that nature being used.......unless i use a 90deg piece of tubing that turns close to the impeller...then that would restrict the airflow i guess... maybe i'll get my machinist to knock something up...
Btw John,turbo is 10" across on the inlet,cup is normal... :lol:

Red,

How do you find the Holset turbos for spool up and do you think their legendary durability makes them better suited to this type of pre turbo injection?

Paul

I'll tell you when they are running..... I picked Holset for 3 reasons.Firstly they are on a million diesel engines that last forever,and they were able to custom build and size for my application,and they are here in the UK........
IMO the 360deg bearing that is in these turbos is so much more durable than any roller bearing.It's force fed with a constant oil supply for starters.

how is the car getting on ? Are you still injecting pre turbo ?

Scott

I was a bit wary of posting this since this is a water injection specific thread, but this is something very relevant to me so I wanted to ask you guys since you are very knowledgeable.

I have in my possession a propane injection kit that was put together for me by a very well known injection specialist best known for their nitrous systems.

Having read through this thread I was wondering how effective it would be to inject propane pre turbo. Injected as a liquid under pressure it would turn gaseous 'instantly' especially since it boils at less than zero (centigrade). Whilst it may not offer much cooling as a result, it would consequently have no opportunity to condense in the intercooler, would offer a denser air mixture at the turbo, increase octane content, would not interfere with a hotwire MAS in blow through and could theoretically be used in tandem with water/methanol injection at the throttle body.

What do you guys think?

That's not a bad idea. Anyone else want to comment on that?

Propane is normally injected as a gas once it leaves the nozzle (restrictor). Almost turns to gas instantly due to pressure drop on the other side of the orifice.

Propane in gaseous form has little or no coolng effect. The resultant charge temperature will be the ratio of propane mass and air mass. Since you will not be injecting a huge amount of propane relative to air (mass% <10P/90A), the drop in charge air temperature is not that great - most people are reading into the marketing hype too much.

The flash point is at its most explosive when the A/P mixture is at around stoichometic and feeding the mixture pass a hot wire sensor can be risky. I am not an expert on this but I would ask the propane injection specialist first before implementing the set up on your car.

Richard

This article towards the end mentions pre-compressor injection considered for hypersonic planes of the future. :lol:

http://www.afa.org/magazine/dec2003/1203spaceplane.asp

I guess we're on the right track, eh?

Excellent find.

I will gibve them a call :lol:

This is some very interesting reading.

it's been a while since i posted here but i have heard on good authority that high end turbo cars on pump gas are going with pre turbo injection.Richard,did you get those castings done? if not have you got an adaptor that will allow the plastic pipe to go through the inlet pipe without leakage of air?
some pics of the install as it is now,water injection is into the plate under the throttle body and into the intake pipe(not shown)....
http://www.phasechangeracing.com/pics/frosty28.jpg
http://www.phasechangeracing.com/pics/frosty27.jpg
http://www.phasechangeracing.com/pics/frosty25.jpg
http://www.phasechangeracing.com/pics/frosty29.jpg
http://www.phasechangeracing.com/pics/frosty8.jpg
http://www.phasechangeracing.com/pics/andyheader2.jpg
http://upload2.postimage.org/192001/...oolerpic08.jpg
http://upload2.postimage.org/192003/...oolerpic05.jpg
http://upload2.postimage.org/125934/...erb0474dc4.jpg
http://upload2.postimage.org/192007/turboside10.jpghttp://upload2.postimage.org/192028/...oolerpic07.jpg
http://upload2.postimage.org/192029/...oolerpic06.jpghttp://upload2.postimage.org/192038/...oolerpic03.jpg

WI nozzle placement and BOV....
http://upload2.postimage.org/197201/bov04.jpg
http://upload2.postimage.org/197205/bov02.jpg
http://upload2.postimage.org/197210/winozzles04.jpg
http://upload2.postimage.org/197215/winozzles03.jpg
http://upload2.postimage.org/197217/bov05.jpg

Andy, what a nice set of pictures.

I look forward to read them carefully in the weekend.

Thanks for posting them.

I was not able to see the images in too much details.

Did you allow the full pattern of the jet be developed - the core shape of the spray should not be touching any bore surfaces.

Here is a spray pattern of our jet (if they are the ones you used)

http://www.aquamist.co.uk/forum/85.JPG

mmmmm,they look like the ones i have.......i'd say the bottom one no...the 2 side ones yes...maybe i can delete the bottom one and rely on the 2 side ones? don't forget there is 4 in the plate under the throttle body....and we can add a boss at the top of the pipe for a straight shot into the throttle body.....did you ever make those bosses for the pre turbo WI jet? i;d like to try that.....

Quick question: if the nozzle forms a "cone" spray pattern in a fine mist, wouldn't that mean that spraying directly at the turbo, even if it was mounted right on the inlet, would result in the water droplets hitting the blades?

I'm trying to imagine spraying at the compressor nut. I'm thinking a "stream" instead of a fog would be necessary, in order to fling the water off to aid atomization.

Nozzle placement & order of activation
 

Digging this thread back up because it's quite interesting and informative.

This summer I'll be running a dual stage water/meth setup (1/3 water-2/3 meth) with one nozzle before the turbo, spraying directly into the compressor and one nozzle after the intercooler, spraying into the upper intercooler pipe. My question centers around the order of activation of these two nozzles. Should I activate the pre-turbo nozzle first (~15 psi) to cool the incoming charge and the post-intercooler nozzle second (~20-25 psi) to help with knock supression? Or am I thinking backwards on this? Any input or suggestions would be GREATLY appreciated.

I'm shooting for ~30-35 psi on a 2.3L (stroked 2.0L Mitsu 4G63) and would like to run 93 octane, but have access to 100 octane if necessary. I'd be glad to supply any additional info about the setup if it's needed.

Re: Nozzle placement & order of activation
 

Your logic makes sense.
You should also think about the relative size of the nozzles, as they are directly related. The more the first one sprays, the lower the compressor discharge temps are bound to be. Also some of that water will still make it to the chambers, reducing the need for a bigger nozzle post-intercooler. :wink:

Ambient temps and fuel octane also play a major role obviously, in the winter with race fuel you'll need smaller nozzles compared to pump fuel in the summer.

I'm experimenting with a similar setup by the way.

Re: Nozzle placement & order of activation
 

I'll actually be running two similarly sized nozzles, but being that the pre-compressor nozzle won't have boost working against it it'll see full pump pressure (if not a touch more due to vacuum). The post-compresor nozzle will have anywhere from 25-35 psi of boost pushing against it and thus won't "seem" as large as it actually is.

So John, would you recommend activating the pre-compressor nozzle first, and the post-intercooler nozzle second?

Re: Nozzle placement & order of activation
 

That's very true. The precomp nozzle will flow a bit more compared to a post-comp nozzle of the same size.
There is actually an older thread where we calculated that difference.
It depends on how hard you drive your turbo(s) I suppose.
If they are pushed way out of their efficiency islands then I'd start precomp injection a bit before they start getting outside the manufacturer's max boost intentions. But all this is experimental you see, we are all learning from our own (and those of others) mistakes. Hopefully.

Re: Nozzle placement & order of activation
 

This will be a single 50-trim Garrett/Mitsu hybrid turbo (Forced Performance "Green").
http://linux.forcedperformance.net/m...Code=DSM-Turbo

At higher boost levels on a 2.3L the compressor will definitely start moving out of its efficiency range. Looks like I'll inject with the post-intercooler nozzle first, and then at higher boost levels I'll kick on the pre-compressor nozzle to move back into a more efficient island on the compressor map. God, I love this stuff! :lol:

That is the way I would do it. Only do the pre-turbo spray when it will do you the most good --- to get that last 10% or so of flow out of the turbo compressor.

Larry

Richard, just wondering if you've made any progress on these or if you plan on releasing them any time in the future. If so, you've got one interested buyer here! Also, what diameter(s) do they come in?

I'm dead-set on successfully using pre-compressor injection, just don't want to be replacing the compressor wheel every year or so. My setup as it stands now is very close to spraying directly into the compressor wheel, but there may be a bit of spray pattern to intake pipe collision as the nozzle is a bit farther away from the wheel than I'd like.

hey guys,

i have been trying to tune my 1985 mazda rx7 which uses an elford turbo kit.

the set up uses an S.U. Carb before the turbo, which is a garret T3 A.I resurch which has sheilded beraings to protect from fuel contamination to the oil.

as a stock car the setup delivers 160Hp at 5psi of boost.

curretly my car is running 16 psi with no intercooler using pre turbo methanol injection, there is no lag. from cruse to full boost in one second.

the methanol has allowed me to use loads of timing and act as a fuel suppliment to allow me to assist in fueling the car.

i hope to get the car on a dyno soon to test its strength.

http://upload3.postimage.org/230613/elford1.jpg


http://upload3.postimage.org/230615/elford5.jpg

any one else playing around with anything similar?
:roll:
Ollie

So you inject pure methanol pre-compressor?

It evaporates pretty damn fast, but I wonder if there are any safety concerns with pure meth. :?

I've been researching the subject heavily again, even bought papers on the subject. Those are aimed at aircraft or power generator compressors, but the fundamentals are the same. Demineralised water is the only substance used though in the experiments, so how methanol behaves is anyone's guess.

The water droplets boil by the way inside the compressor, once they enter the areas of extremely low pressure. So water never makes it into the diffuser, only steam. We're talking water/air ratios of up to 5% here, which is far more than any of us have used - I've only gone up to 1.5% (by weight)

Steam is useless for in-cylinder cooling by the way, there is no phase change left that we can take advantage of. I was suspecting that, hence my setup with an extra nozzle after the intercooler. Steam actually displaces oxygen in the chambers (not good) but because this happens after the compressor no oxygen molecules have been traded off. This may explain the boost increase which is observed as soon as precomp injection kicks in)

Olly may not be able to reply at this time but he does inject pure meth pre compressor as well as meth with no intercooler. It works very well. He runs no BOV which limits the gear changes but over all gives him loads of scope.

Its true steam does nothing but methanol atomises at a lower temp and does not change state after atomisation
Scott

JohnA,
Just trying to get my head around what you were talking about the steam.
1. port injection is good as cylinder get to see water droplets 5-20 micron in size
2. evaporative cooling is good as it cools the air down until saturation point is reached
3. steam what produced in intake system and not absorbed by air is bad as it ?replaces? some of the air in the system?
Basically speaking all excesses water that does not get absorbed due to the system been past saturation point and which boils up is bad?

Water replaces air too. It's harder for the frame front to travel around larger water particals.

Okay, this may be somewhat of a new approach in some respects, but could those of you with some thermodynamics expertise bear with me on this one and give me some input.

Going right back to the beginning of this thread and trying to incorporate as much of the theory as I can from the wealth of knowledge that has followed on, I have grasped these main concepts.

(1) Pre-compressor injection is unique in that it can increase compressor efficiency by pushing compression away from adiabatic towards isothermic (I hope I got those terms correct);

(2) Whilst larger volumes of liquid injected pre compressor may reduce temperatures by a greater amount at the compressor, a point of diminishing returns can be reached because (a) this may reduce intercooler efficiency resulting in intercooler outlet temps increasing and (b) saturation occurs whereby no more water can evaporate and consequently no further heat can be absorbed.

(3) Therefore, ideally we want to inject just enough water to achieve (1) without inducing either of the diadvantages of (2);

(4) Water has the greatest ability of all substances injected to absorb latent heat; and finally

(5) In order to prevent or at least substantially reduce compressor blade damage we want to inject water droplets of the smallest size possible (ideally 10 microns or less and certainly no larger than 50 microns)


So, a few questions.

(1) Does a mist of water vapour at ambient temperature absorb any less heat when injected than say a mist of water that is chilled to 10 degrees celsius immediately prior to injection?

(2) If the answer to (1) is that cooler water absorbs more heat, then would water injected at it's lowest liquid temperature (i.e. 1 degree celsius) be more or less effective in absorbing heat than the same volume of an alcohol and water mixture that could be injected at below the freezing point of water?

The reason I ask this is that people have been injecting propane instead of water pre compressor for years. Propane enrichens the octane level of the final fuel mixture as well as expanding at a phenomenal rate which reputedly also helps distribute fuel in the combustion chamber better, which in turn leads to fewer hotspots.

As such it also suppresses detonation but NOT by reducing the temperature of the intake charge. Injected for the most part as a vapour all the cooling effect takes place at the propane container which becomes cold to the touch, but the cooling effect on the intake tract is minimal.

Okay, this is where it starts getting interesting. Forget safety issues for now, I am not interested in those for the purposes of this discussion. During actual application yes, but NOT here. I have a Propane Injection System which uses a solenoid at the injection point (like a nitrous system). The bottle is inverted and the delivery line once purged of vapour remains under pressure prior to injection. Propane is thus injected as a liquid. Propane 'boils' at -40 degrees (that coincidentally is roughly the same in either fahrenheit or degrees).

Since it becomes a gas almost instantaneously it probably won't absorb much latent heat - accepted

It does however have an octane rating of around 110 which means it really can replace any fuel it displaces although it takes up a considerable volume of 'airspace'.

So suppose we used a nitrous wet fogger injector which simultaneously injected liquid propane at 40 degrees below zero together with a water and alcohol mixture (composed of the greatest percentage of water possible that would not freeze) and injected it pre compressor.

I can see a number of possible issues;

(1) Catastrophic impeller damage created by a phenomenal change in temp from several hundred degrees to -40
(2) The mixture is unable to absorb heat;
(3) Temperature differential results in condensation and compressor damage;
(4) Loss of intercooler efficiency; and
(5) The fogging effect even under 400 plus psi fails to atomize the liquid to less than 50 microns.

However, given the number of devices used to reduce air intake temperatures and the advantages of isothermic compression, I would think that there must be some merit in this idea even if the injection point needs to be re-evaluated.

I'd value your comments.

Paul.

two different things:

Port injection is a better version of injecting at the throttle: it provides mainly in-cylinder cooling

Precomp injection provides minimal in-cylinder cooling, but it reduces charge temps a lot and allows the turbo to spin slower for the same boost.

One does not exclude the other - i.e. you could have both. (I do)