Alcohol/water injection turbo diesels.


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For those who are not aware of the benefits here it is in a nutshell.
• How does alcohol/water injection work?
By injecting a fine spray of alcohol/water into the inlet air stream of the engine, the charge air is dramatically cooled and the effective octane of the fuel is raised. Both help to eliminate detonation — the enemy of any engine, especially those using today's lower octane fuel under boost. For turbo diesel engine you will get a 100% fuel burn and on average pick up 20% to 30% more horse power over your RPM band. Turbocharged Gas engines will on average pick up 20% more horse power. You will notice immediate gains in performance. Your turbo will spool up faster, your top end will be noticeably improved and you will get no detonation.
What are the other benefits of alcohol injection?
1. Steam cleaned motor, alcohol injection will remove 95% of all carbon on the inside of your engine and keep it that way dramatic increase in engine life. There is no fuel additive on the market that can clean your engine as well. This means less maintaince , were talking almost zero carbon build up on plugs combustion chambers and valves!
2. Eliminate black smoke in turbo diesels by 95% under load.
3. Reduce emissions making a marked improvement in air quality.
4. More Kilometers per liter, more power at less throttle equal more liters per Kilometer.
5. Zero detonation
6. Intake air temperature reductions of up to 37C drop. You touch your intake it will be ice cold even on the hottest day after the system is on.
7. Reduction of Exhaust gas Temperatures as much as 93C, which increases horsepower and eliminates detonation especially on chipped vehicles with increased timming and boost.

Common question will injecting water/alcohol into my motor harm it, This is a complete myth water is produced in the combustion process in rather large amounts already. Methanol or whatever alcohol you choice to use is in vapor form inside the engine due to it's low boiling point. On diesels you can only go a max of 50/50 on the water/alcohol mix.

A alcohol/water injected motor will be free of about 95% of carbon buildup and stay that way as long as your using it.

Fact about water production in internal combustion engines.

Look something like this for each 100 gallons of gasoline burned diesels are similar.

90-120 gallons of water
3 to 10 gallons of unburned gasoline
½ to 2 pounds of soot
¼ to 1 pound of resins and varnishes
1 to 4 pounds of nitrogen and sulfur acids
6 to 10 ounces of insoluble lead salts (if leaded gasoline is used)
1 to 2 ounces of hydrochloric and hydrobromic acids.

If you don't believe it then feel free to look it up.

Now some dyno's these are both 2.5L engines mechanical pumps no electronics.

This vehicle is bone stock no modifications but a cold air intake. No boost controllers.
Guess what folks this is done with the factory intercooler completely by- passed. We completely ditched the factory intercooler, There is a DO1gph nozzle pre turbo which you can see from the charts the resutls of the instant spooling it provides even with 100% water the TQ off the line is impressive and a DO2gph nozzle at the intake to further cool things down.

Now a DO3gph nozzle at the intake would work just as well on most vehicles but this one struggled to make boost so we did pre-turbo which makes the little turbo act like a big one.

We did pulls with 30/70 methanol/water and then switch over to 50/50 denatured because the meth was already mixed at 30% gains probably would have been even greater with the methanol.

Note the mixture was 30/70 methanol/water if it is not stated on the dyno sheet. The other mix we use was 62P bottle of Ethly alcohol from the drug store 500ml and 500ml water for the 50/50 mix. The gains were larger
System activates at around 1400rpm on this 2001 Starex

Note 30lbs or around 40nm tq that you have at activation of the system even with 100% water vs the stock. This is the pre-turbo injection benifit. Little turbo acting like a bigger more efficient turbo.

Here is a comparison of different activation points with 30/70 methanol /water..

TQ numbers
Notice the 50lbs or 67nm improvement at 1500rpms and 38lbs or 51nm at 2500rpms.

This is were we change it up to 50/50 mix, The methanol was already pre-mixed so we had to go with ethyl alcohol which I bought for 62P in a 500ml bottle. Gains will be higher with methanol because it has a higher octane number and better cooling.

Once again 50lbs more TQ AT 1500rpm the turbo spools up instantly when the system starts to inject. The effect is instant torque at low RPM's.

Bottom line 18% more power and 23.5% more torque on this pretty meager engine.

Diesel have 20% to 30% unburnt fuel even a ratio of 15% alcohol will significantly reduce your emissions by giving you a 100% burn and the extra power is just a bonus.

Here is a Mazda MPV that just installed the kit and the dyno results from last month.

Great results at 1500 to 3000rpm power and torque increases are great but the turbo does fall flat on it's face at around 3600rpms a pre-turbo nozzle would give you alot more gains in your top rpm range.
But look at the max gains.

1500 rpms 14hp TQ 47LBS Max HP Gain 43% Max TQ gain 46%
2000 rpms 32hp TQ 84LBS Max HP Gain 63% Max TQ gain 65% HUGE!!
2500 rpms 17hp TQ 36LBS MAX HP Gain 20% Max TQ gain 21%
3000 rpms 10hp TQ 19LBS MAX HP Gain 10% Max TQ gain 11%
To give you a ideal how well the system is working when you just look at the gains on just water alone it's enough to be impressed.

1500rpms 6.3hp gain- 20% over stock / TQ 22lbs 22% over stock
2000rpms 18hp gain - 36% over stock / TQ 47lbs 36% over stock
2500rpms 12.5hp gain- 15% over stock/ TQ 26lbs 15% over stock
3000rpms 6.9hp gain- 7% over stock/ TQ 12lbs 7% over stock

Even just using water give you good gains and if you want more power just add some alcohol to the mix and you got it. There is simply no modification for the money that can do this and all without changing anything about your engine. Even on pure water you get marked improvements in acceleration and fuel economy as well as reduced emissions.

As we stated before these vehicles have undersized turbos and the pre turbo injection signifiacatly helps them with the top end power Just compare the starex dyno. If he puts on a Pre turbo nozzle the power up to will be much greater.
All in all very impressive must be a blast to drive compared to stock.



Just something to look into. If your chipped or remapped you will gain even more power and keep your EGT's down to a safe level which 780C is about the max sustained EGT's you want. High EGT's are a common problem on turbo diesels and can lead to engine and turbo failure.
Thank you for that VERY useful post - sorry it got held in the moderation queue because it contained pictures. Welcome to TorqueCars its really nice to have you along. You know a lot about Water/alcahol injection then.
Very interesting post, one querie, i thought it was beneficial to have a small amount of carbon buildup, what you describe sounds like bore wash to me, I wouldn't have thought that was good.
Water injection is quite a common feature on Rally Cars for exactly these reasons - ie. massively lower intake and exhaust temps.

I can vouch for the cleaning properties as well. Have you ever seen the cylinder head of a car that's had an internal water leak. It's completely obvious which cylinders have been subject to the leak as they're shiny clean like new.
the build up of carbon is healthy on older cars as it seals up any pits and wears on the cylinder. thats why its not normally advisable to flush a old engine otherwise it may run worse than before rather than better
I actually own one of the water injection companies, One of my friends refered me to this site to pass the info on. There are however 3 or 4 other major makers of these kits and you can feel free to check out them all.

The results will be pretty much the same on any kit by any kit maker it's just about how much you want to pay for your system and how you like the individual set up.

Carbon does not hold any benefits in the modern internal combustion engine.

Carbon build-up on top of the piston or on the cylinder walls may also cause preignition. This would give similar results to the cooling system issue. The carbon buildup could be because of running extremely rich for any length of time. Therefore, when repairing high CO emissions failures, always assume that carbon has formed. Oil consumption will also cause this type of carbon, which will also cool the combustion chamber temperature. Carbon on the throat of the valve will absorb fuel, causing a lean condition and giving a similar result as to the previous lean condition.

It will also build up on valve seats as well, The exhaust valve-seating surface is not just to seal the cylinder airtight, but to provide a means of removing heat from the valve and disbursing it to the cooling system. An incorrectly seated exhaust valve will not transfer heat. Consequently, the valve and its seat will rise in temperature, causing preignition. This will result in high HC, high O2, low CO, low CO2, and high NOx.

There's a whole laundry list of stuff caused by carbon and soot build up, eliminating that means leas engine wear no matter how you look at it
I have to say that relying upon spurious carbon deposits to help 'seal' things sounds like a very inexact science.

I'm not sure if your refering to what I posted, I am saying that carbon deposits on valves cause them not to seal and the listed problems. When your valves are caked in carbon your going to have problems such as a detonation, and incresed emissions.
I agree that carbon is bad. It causes hot spots in the engine. I think HDI was making regference to the previous post. I think there is a commonly held belief that carbon increases (improves) your engine compression preventing blow-by in the cylinders. In reality though I don't think a layer of carbon in the cylinder will make much if any contribution to the compression.
yeah i think he was replying to my post. its more very high milage engines or ones that havent been looked after and have a lot of wear and tear on the internals. the build up of carbon, yes ill admit is now sounding bad, but it seems to help the engine
As an ex rolls royce engine builder, (diesel) it was advised when doing a de-coke, to leave a ring of carbon around the top of the pistons and head
Thats interesting, so there is some truth to the rumer then. Any idea why this was the case?
This is a debate that will continue ad-infinitum. I'm guessing that if an engine is already extensively coked then the removal of all of it could lead to sealing problems.

However, if coking is controlled by virtue of good operating conditions (ie. quality fuels, good maintenance and not too much short distance driving) then it's best to keep things clean.

I've never yet heard anyone say that it's a good idea to skip a couple of services, use the wrong grade of oil, fill with poor fuel and drive stop start for five years in order to build up a healthy deposition of carbon and other associated by products of poor combustion.
I also think everything has changed since my day, better fuel, fuel injection, ecu controlled, and better engine designe, when was the last time you needed to take the head off to do a de-coke:bigsmile::bigsmile:
Just to get it back on topic.

Yesterdays Dyno

2000rpms 11.4hp 29.9 lbsTQ
2500rpms 9.5hp 17.4 lbsTQ
3000rpms 15.6HP 27 lbsTQ
3500rpms 17.8HP 26 lbsTQ
4000rpms 18.2HP 23 lbsTQ
4500rpms 28.2hp 32 lbsTQ

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I asked about that two, Could just be how that engine is. Should be no reason for the drop off unless they had some air left in the lines or did not put a vent hole in the tank.
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Having a little fun with alcohol, Yeah you can use brandy, gin, vodka it all works the same :lol: Just make sure it's less than 50% per volume.

He is only running a 3GPH nozzle were going to fit it with a D04 nozzle for the next dyno. It just goes to show you can run as little or at the max to get the best between power and water alcohol consumption.

1500 55 65.4 65.1 64.2 10hp
2000 105.3 111.4 112.1 109.3 6.8hp
2500 119.5 130 128.7 125 10.5 hp
3000 122.3 134.2 135.3 130.3 13.3
3500 120.7 136.6 127.4 128.1 15.9
4000 108 126.7 127.4 121.2 19.4hp

1500 194.3 227.9 33 LBS
2000 276.5 294.4 17 LBS
2500 251 270.4 19.4 LBS
3000 214.1 236.9 22 LBS
3500 181.1 206 24 LBS
4000 141.8 167.3 25.5








I have to disagree with one thing dvldoc has said...
water/meths injection on diesels doens't have to be a max of 50/50
you can use pure meths and get even more gains
theres a bloke with a 205 dturbo (with and engine out the 306 1.9td's)
and he uses pure meths no problem
I'll try and find the article for it...
how much would a basic set up cost ?
done a search for one and found a system than fits into the inlet manifold for £480. that was specifically for the VAG 1.8t engines. inc bottle, 2 nozzels, micro switch, and pump designed for current power levels

not looking at it now as not high on boost but might be interested further down the line
If it was desgined only for your engine i reckon you can't go wrong there...because the people who made the system as fitted one onto your engine and tryed and tested it

£480 sounds about the going rate, who makes it?

I know Aquamist are surposed to be good
just searched on google for water injection and it turned up a german company selling them. it worked out around £480 but that didnt include delivery and obviously i would have to fit it myself or get someone to do it for me.
cant remember the name and can find it now.
like a said im not really looking at this point but may look in the future
good info about diesels, my opinion is water/alky fine for DI diesels, but not good for IDI engines.

i have a W/A system on my 82 Isuzu 1.8L turbo, if i go over 25% Alky, it knocks like hell, my conclusion is the alky is detonating on top of the piston, while the D fuel is being injected into the combustion chamber, IDI engines have a combustion chamber in the head 90% of chamber volume.

the alky is injected into the manifold not into the chamber.

it will be interesting how W/A will be on modern DI petrol engines, alcohol is a fuel and can detonate, before fuel is injected!!??

question; will we see a water injector in the actual chamber??

things could get REAL expensive!

I have tried Nitro before and the gain were impressive to say the least...I used a 25% solution but I mixed water with it as well so wasn't really 25% after that, It was a Mix of Nitro and Methanol which I bought from an RC car shop
hey, jarrus you might rethink how the combustion process of a diesel engine works.

100% alky and 30psi manifold pressure, that sounds like a race only type engine!

if you are using diesel fuel in any engine you have to control rapid burn, or you get knock, in other words you want slow combustion process.

if you have ANY TYPE of air/ fuel entering by way of inlet valve(ie;air/alkohol) you may/will get preignition and knock, alcohol is a fuel. yes hi octane ,but never the less a fuel.

this is why modern petrol engines are moving to Direct Injection,directly into the chamber, at a precise time.

as you do know DI engines have no fuel/air on the suck stroke,only air,air cannot burn without fuel, and with proper chamber design, we can control the expansion process, so have a slow rise in chamber pressures= quiet, and smoother stress on internal components.

on a IDI diesel chamber, when D fuel is injected into the prechamber,it starts a burn, if you have any type fuel in the area over the piston it will expand to rapidly and cuase a spike in cylinder pressure and make a knock along with high stress on parts.

with a DI diesel that is why roughly any thing over 50-50% water/ alko will have noise and possible future problems, yes OK for short periods of time, but not a favorable street vehicle.

any way give it some thought, and ask any auxialary injection system manufacturer.

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