kenc

iTrader: (6)

Hi guys, have been thinking of getting aquamist water injection on my 00 sti 4dr, i have read that it brought project wrx inlet temps down by almost50% on the jap performance feature, has any one got it????? is it good???? if i fitted it would i get power gains??? also i downloaded the fitting instructions and jet is to be placed b4 throttle body, but on scoobys, gtrs celicas etc that have the heat soaked tmic that jet has to be placed before intercooler can any 1 give experienced info??? is ther any bad points to it???

Trout

iTrader: (1)

Water injection can be excellent.

I used to use it in my car on track and it really made the performance a lot more consistent.

To fit it you need to consider a number of things.

Safety or power?

Water will enable more power, or keep things cooler for lots of high pressure running like on track.

Simple boost switch or mappable?

A simple boost switch will turn it off and on at predefined boost settings.

Mappable will give a 3d map against boost, temp or throttle position and engine speed. Greater control - much better 'proportion' of water going to the inlet system. More tuneable. You will need to introduce up to 20% of the volume of the petrol to the system. This is so much easier to map if you have the fuel map of your car.

You will need to set up a water system so you will need a tank, probably boot mounted if you are serious.

You will probably need an ECU map. When I fitted water I got a lot more power though increased advance and around 3% less fuel.

On a Scoob you can fit water in two locations. Pre-intercooler to cool the intercooler. Also pre-throttle body to cool the charge temp and cylinders.

If you do both you will need two pumps and each one will need to be mapped separately. Something like a 5% charge to cool the intercooler on a boost switch then a mappable system on the throttle body.

Aquamist is the way to go and most other kits are rebadged Aquamist parts.

kenc

iTrader: (6)

i would be going for basic system boost activated, which would give better results b4 intercooler or after??? i only want it for odd drag, no track days, does this do away with need for octane booster????

RB5_245

If you inject pre intercooler you the water is suspended in the air, at sharp changes in direction, ie in the cooler, this will act as a water trap and take the water out of supension causing it to form drips, and will 'run' into the engine unevenly.

If you fit it without mapping for it you will see an instant power drop. Using it with my TMIC saw power drop from 340bhp to 330 on back to back runs with the road dyno.

If you map for it (you will gain power), and the tiny nozzle clogs up (which it can do easily) you'll get detonation and loose your engine quicktime.

Use it as a safety barrier to hold charge temps down if you do track days, but there are more reliable ways to get more power.

Dave

BVM

Water alone will only help lower the chance of detonation. Since water is not a combustible medium, you will feel a miss or stumble when the system goes active.

Water/Alcohol will give both a slight power increase and improve detonation resistance.

Water/Meth will give much more power and improve detonation resistance.

You need to install the nozzle as close to the T/B as possible. If you have a TMIC, install the nozzle right before the TMIC to T/B hose.

If you want power you are going to have to map for it if you want the most out of it. Alcohol and Meth will make your car go super rich. You can play with the mixtures to help out there. I run 50% denatured alcohol/ 50% distilled water.
Several systems have clogged nozzle indicators or fail safes so make sure you pick a system with that feature.
Once you go chemical intercooling, you'll never want another turbo car w/o it!

Peanuts

iTrader: (15)

I disagree with a couple of points made above by BVM.

BVM

LOL you are more than welcome to. Though just stating you disagree w/o giving a reason makes no sense.

RB5_245

I've found water alone to give me a small % power drop but no adverse effect on smoothness.

If you install too close to the throttle body there is a chance of not getting full dispersion(sp?) of whatever you're injecting. To far away and there is a chance of dropping out of suspension and forming droplets at tight bends/direction changes.

impreza_terzo3_no257

on my scooby ive got a 5 ltr water tank in the back and the water injection kit, and its constantly on, not really kept an eye out on temps but just boot if you know what i mean

BVM

Good concerns. Nice to chat with someone that has a clue!

The ideal placement for injection is within 3-6 inches of the throttle body.

Depending on the amount of water (and at what line pressure you are using) usually determines if you will notice a slight hesitation when the system engages. I prefer to use progressive controllers that vary pump pressure- dependant on boost. Either way, water only, introduces a non-combustible into the combustion chamber. You should be able to detect when the systems goes active since it will usually cause a slight hesitation. Normally you can map around it but most don't bother.

Peanuts

iTrader: (15)

I shall elaborate
technically correct but the implication is that you need methanol as well, my experience is that with increased resistance to DET, timing can be advanced and the by-product is more power.


In my experience the wideband has shown with the addition of methanol/alcy-hol to go super lean on the reading. In fact a normal idle reading of approx 15.0:1 shot straight out to nearly 16.7:1 with a 5% mix.

I wasnt being cheeky, I just disagreed a little with my own experiences

BVM

Actually you have that backwards. Unless you didnt reset stoich when using a wideband with alcy or meth. Obviously each has their own values. You did know that, correct?

Yes you can run water injection w/o meth, but you will not be able to take advantage of the octane boosting properties of methanol, thus you will get cooling from the water, but no increase in octane. Without methanol, you may not make as much power, as it acts as a detonation inhibitor, and you may not be able to run a leaner AFR as you could with it. You also must note that meth can damage seals in older cars.

I prefer to use denatured alcohol since its much easier on the seals and easier to tune for.

GC8

What mixes would anyone recommend (water + isopropyl alchohol and water + methanol)?

Simon

Midlife......

iTrader: (2)

Simon

I'm going for 50 / 50 Methanol and water ....... I'm a simple northener and I can cope with the maths...LOL

Shaun

Trout

iTrader: (1)

BVM,

you are not entirely correct. With water alone you will get an 'apparent' increase in RON as you say yourself you will get protection against det.

Additional resistance to det is like adding an octane booster. You can then map in MORE advance and therefore get more power.

With water alone you can reduce the fuel amount and increase advance and get a reasonable increase in power.

A water/methanol mix actually increases power more and it increases thermodynamic efficiency more than water alone. However with too much methanol you get the same heat issues as you had to start with as methanol burns hot!

I would say that water alone gives you 1-3 RON equivalence.

The downside is that if your jet blocks or your pump fails or your water runs out then det-det-det-det!

BVM

I disagree. Water has no octane boosting values... its water aka a non-flammable liquid. What it does is lower the combustion temps allowing more advance but certainly not by any other means. I have never stated otherwise.
Adding denatured alcohol or meth to the mix is where you start making power due to the added octane.

RB5_245

Ahh, I see what you mean by hesitancy. I was thinking maf failure symptom yes if you flick it on at wot you notice a straight (slight) drop in power.

I use aquamist with a 0.5mm nozzle so not progressive and only small % added water.

Have to say though that adding water slows the flamefront helping reduce det. For this reason water content in F1 fuel was strictly controlled in the turbo era, and large diesel manufacturers are testing with emulsified fuels to improve efficiency and increase outputs.

Dave

Trout

iTrader: (1)

You infer that water 'will only' lower the chance of detonation whereas water/methanol gives a 'slight power increase'.

Adding water injection alone can give a power increase due to being able to advance the ignition curve.

Your point is true if you cannot remap the advance curve - however if you can change the ignition and fuel maps then water alone can be used to give a reasonable increase in power.

With methanol you can have even more as you state.

Regarding the engine 'stumbles' when the water is added it may not just be water in the engine. If the fuel map has not been changed the engine will be running a lot richer. The lambda values fall quite a lot when water is added. The bonus is that even with water being non-combustable you need less fuel.

Maybe we will just have to agree to disagree. I can only go on my own experience with this system, your mileage may vary

BVM

LOL its all good. I like technical debates!

Water alone its really only for det suppression.
Can we agree on that?

Water injection can be used even if the car has not been mapped for it even though it may cause a slight hesitation when the system goes active.

Water/alcohol is det suppression with a mild hike in power (if mapped for). Can we agree on that?

Water/Alcohol can be used but 90% of the time will actually cause a power LOSS, UNLESS you can lean out the AFR's to account for the alcohol. Leaner AFR and added spark is where you make the power with alcy injection.

Water/meth is for det suppression with a fairly substantial increase in power (if mapped for).
Can we agree on that?
Same principals apply with water/meth as alcohol.

100% meth or 100% alcohol used without tuning is a major no-no. When the system goes active you will run mega rich, I am talking 8.1 rich. You run the risk of washing the cylinders and thinning the oil. This will most likely result in catastrophic engine failure.

Trout

iTrader: (1)

Can we also agree that without remapping putting 15% water in (0.4m injector on a standard car) will also lead to the car running quite rich?

Even with basic water you should lean out the fuel - or use less water, say 5-10% for det suppression.

Whether water 'should' be used for an increase in power is a different matter. With water alone you can get 2-3 degrees extra advance which on some cars will be 20bhp and 30ftlbs. That is a lot extra if you are running around 300bhp.

I would not recommend this as a way to get power though as when you run out of water or your pump fails so does your engine!

Do you agree on that

Bob Rawle

FWIW, my own set up.

I use a mappable aquamist system directly controlled by my ecu.

Jet is 0.4, max wi solenoid duty is 55%, engine is putting out circa 510 bhp.

Position of jet was critical as otherwise it didn't get a chance to atomise properly, can't be too far back either.

I use a 50/50 water methanol mix.

Tank is Spec C boost mounted using the bult in pump as the primer.

I guessed a bit at afr's initially and it was "all right", allowed me to run my race fuel ign map as a daily drive. Was too lean in reality though.

Then I actually calced the afr based on the proportional stoich values which led me to richen and imediately was able to add three degrees ignition.

So yes its a benefit but ...

on its own without remapping the car will almost certainly run rich and lose power but gain some safety.

properly mapped to its a huge benefit (based on my project)

if it doesn't work look out which is why I have a separate primer switch so that I can test the system every time I start the car, I know its working as the afr readout kicks rich untill the ecu compensates.

if ever its not working I have a bright red Xmas tree on the dash flashing at me.

My Spec C tank lasts me 3-4 months of mixed use.

Midlife......

iTrader: (2)

Hi Bob

Thanks for the post........very timely as I'm just sorting out with Olly booking my Bugeye into RCMS for what you have described above

Due to your HUGE popularity I hope this should be mid September

Cheers

Shaun

kenc

iTrader: (6)

so guys mayb this is stupid question but could you add meth into your fuel tank, wud it be same as booster and would you get safe power gain