water injection

[Jarred]

hi guys.

just wondering some basics about water injection on my 1.5D.

seen a few things around, but never known too much about it, so I'd figure I'd ask here.

From what i can gather, ti's literally just water being sprayed along the inlet tract at some point, with the point of gaining more power.

if this theory is correct, if I got out side with a spray bottle with water in it, take off the air intake and air filter, and spray some water down the manifold, (with the car running) is this going to give my car a momentary boost in power??

will it damage the engine? does the fueling also need to increase?

it's a pretty broad subject, but I know a few people out there know something, and maybe it's something i'd like to give a go sometime (soon)!

[Tim]

the idea is to cool the intake charge. not to drown the engine. Im pretty sure you are required to run a bit higher pressure to mist the water than what your spray bottle will be capable of

There are a few websites out there that explain the basic concepts. But yeah.. Less knock allows more advance/more boost/higher compression I believe is the idea

[Greg Roles]

The biggest thing it will do is to cool the charge. Unless you have a temp sensor that then injects a bit more fuel via a computer controlled ECU, it's going to do very little. On an older diesel you can then adjust it to add more fuel, but when the water runs out, it's going to blow smoke as it's now too rich. You need a way of factoring that in. Also, as Tim mentioned, you need to have a very high pressure pump and specific nozzle to really atomise the water, a squirty bottle is a ways off that, but give it a go in moderation.

The downside is that water then displaces oxygen, and you have less in the chamber to combust, so it's kind of a catch 22, more in there because it's more dense, yet the water itself is displacing oxygen.

Bottom line if you add some Methanol in a 50/50 mix, suddenly you have an extra fuel source that won't ignite till the diesel does, and this will generally liberates more power.

In a non intercooled diesel it would be a great move. It's definately something I'm going to have a go at, with a specific diesel setup.

[gldgti]

The biggest thing it will do is to cool the charge. Unless you have a temp sensor that then injects a bit more fuel via a computer controlled ECU, it's going to do very little.

sortof, but really, you can simply put your foot down further. the old injector pumps are very basic, and the only thing that limits fuel is the RPM govenor. they are so slow that there is oftentimes a place a long way from full throttle that is max power for any given rpm, so if you can make the charge cooler or denser, all you need to do is use more throttle to get that extra power. its called "driving by the shade of your plume"

Jarred, go have a good look and search around on www.vwdiesel.net . there are quite a lot of guys running water-meth over there from washer bottles.

[Jarred]

I just wanted to a rough idea of what's involved and what the benefit/s is/are.

i'll have to do a bit more reading and give it ago I think.

[JustMark]

Hi Jarred

If you look at the end of the how to tachofy your mk1 you will see i added some picture of how i did this on my mercedes 300d.

I too have been researching how to set this up on a 1.5d mk1. I have been running the water injection ( with upto 50% methonal) for a couple of months on the merc and i have seen good improvements from easier starting to running quieter, etc.

Also having shaved a few seconds off 0 to 100 times helps a little. But the main reason i did it was to clean the insides as i have been using and making my own biodiesel.

On the Merc there is an auto kick down switch which only turns on the washer bottle when i put the boot in.

I was thinking of doing the diesel tacho mod then adding this

http://cgi.ebay.com/ebaymotors/UNIVE...Q5fAccessories

Along with an aftermarket shift light tacho thats adjustable so that i could use the shift light to turn on the washer bottle at what ever revs i choose. then set it and forget it. Also to try and make it idiot proof as it is my gf main car.

The only other issues i can see with running this on a mk1 is that of the intake port. On the merc there is one intake port that is split into runners, were as on the golf there are 4 intake ports behind the air filter.

Im not sure if the washer bottle would have enough go to atomise four nozzles properly. However there are nozzles that are adjustable within them selves so that they would each have to be set up individually, rather than just once like on my merc. It would be a bit more involved that setting up the merc but if the golf improved as much as the merc did it would definatly be worth the hundred bucks or so outlay.

Mark

[Jarred]

Hi Mark. Your post in the other thread was what got me interested in it originally.

So Far, I've had a quick think, and this is what I've come up with.

Realistically, it doesn't need to be on all time, so I'm thinking of using a set up similar to a kick down switch; a contact under accel pedal, or a micro switch on the IP itself, to switch it the pump at full 'throttle' only. That way there's always enough fuel, and hopefully there wont be any leaning out issues.

With the four runners, I'd probably use two nozzles (one between 1-2 and one between 3-4) as 4 i think would be over kill two, but 1 wouldn't be enough to ensure even distribution. I think the manifold would have to be drilled and tapped on top, to ensure the spray sits down low enough, and doesn't get the air filter wet. hopefully the one pump would be enough to run the two nozzles with a Y piece, or maybe a change in tube size to increase pressure. something like that. (havn't thought about that part a heap yet.)

where do you buy methonol from and are you using distilled water, filtered water or tap water ?

Curious to hear your thoughts.

[Preen59]

Methanol is fairly readily available. Race+Rally or Revolution Race gear would be able to steer you in the right direction. Or buy Dragster Australia, plenty of mobs selling Methanol in there.


If you decide to man up and run a bit of Nitromethane, let me know.. I'm sure we could sell you some. It's about $10/litre but you won't need much..

[oracle1]

Im currenty getting ripped off

I'm currently paying $260 for 205 liters of the purest methanol. I have heard that the drag racers are paying around $210. Water methanol injection is used extensively on gas turbine turbine engines to augment power and reduce EGT's on hot and high days. Higher altitudes and hot days reduce the density of the air so the aircraft has to produce more power to compensate for loss of lift and loss of efficiency within the turbine.

Just be careful that you devise a system that feeds each pot equally. Generally the turbines are fed right at the front of the intake with something very similar to washer squirters but it is all going down the same hole.

[gldgti]

alright, who wants to convince me to do this on my mk3 too

[Preen59]

alright, who wants to convince me to do this on my mk3 too

Nitro??

[JustMark]

I am just running tap water. I think it might be more important to run distilled with finer nozzle sprays to keep from blocking it up.

The only negitive about the system on the merc is that it will turn on at low revs when i put the foot to the floor. If there arent enough RPM it can nail sometimes. Thats why i wanted it hooked up to a Tach with a shift light so the shift light could turn it on at high revs. Plus i dint think the GF ever drives WOT or would ever stick the boot into it far enough so set off a foot activated switch.

I set mine up to run 300ml a minute. This was taken from a merc website, so i guess the Golf would need less.

i bought my Meths in 44 galon drum In bayswater... Wholesale Automatic Transmissions in Bayswater. Barry St I think.

I did see something that caught my interest. Would a turbo set up off a petrol golf work on a Diesel. Aparently its suitable for the 1.6 petrol so it is set up with a carb. If it fits I think i would have to swap the merc with the misses... as i already love that golf too much...

I have a bit of time up my sleeve tomorrow so i might have a play with four nozzles an get back to you.