DIY water injection

Dave

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Hi Guys,

I am thinking about making a water injection kit for my Bx. I know it has been discussed in the past, for both forced induction and n/a. I am looking for advice as to how to constuct a kit that will have the jet/nozzle sit above/in the carb throat and therefore only suck in the water when the throttle is open. What have people used as the jet in the past and what size has given the right flow rate? (5-10% water to fuel i think) I know i will need to fix the fuel mixture after it is installed.
So i'm guessing i will need a bottle (2 litres or so) with tube inserted from the top that then feeds to the carb throat where there is a very fine jet/nozzel that restrics the flow. Also is it possible to set up a solanoid so I can block the system off while the engine warms up therefore stopping the problem of contaminating the oil with water?
Any help would be much appreciated! (i'm looking at Damien Gardner and Pugrambo for starters ;) )

:cheers:
Dave
 
firstly go down to the local supermarket (read tip) and look for any old washing machines and grab some vaccuum switches

they are usually mounted at the top of the machine near the timer and are used for the water level cut out

you then rig this using vaccuum from the engine to turn the power on to a windscreen washer bottle

as for a jet i can't remember what size i used last time but damien will have a pretty good idea

hope that gives you an idea Dave
 
The setup I had was as you describe... a bottle with a hose out the top, a piece of tube araldited into the carby base (below the butterfly, I'm fairly sure...) and along the plastic hose there was another piece of tube with a series of pinholes in it.

You push the hose over this to cover up holes and adjust the flow rate... no pumps, no switches, no problems... saved me about 1mpg.

Putting in a 203 gearbox saved me 1.5...
 
Dave,

The method for stopping water flow on the original designs was quite simple. A 1/8 brass tube with 45 degree mitred end was inserted into the carby base at a point at which it was on the upstream side of the throttle butterfly when the throttle was closed. (These were cars with separate cast iron carby bases. Less courage needed to drill the hole, and more wall thickness to Araldite to). Once the throttle was opened a bit the butterfly moved past this nozzle and vacuum was applied to the system. We used little slices of 1/8 plastic tube placed over the drilled brass tube at the bottle, and between each pair of holes. You could then slide each little sleeve to cover any number of the air inlet holes. These holes control the amount of vacuum applied to the jet in the water in the bottle. The water flow control jet was a short piece of brass rod with a tiny hole drill through the centre. It was inserted into a piece of 1/8 vinyl tubing on the end of the pickup tube in the bottle.

I ran one for a number of years about 25-30 years ago. Didn't find much difference between pure water and up to 50% metho, therefore only added metho when going to the snow to stop the bottle freezing. Still got alot of the bits in the shed somewhere, I think. Can't remember the jet (drill) sizes, but can dig it out if needed.

Cheers,
Warwick.
 
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EMC,

The water is sucked into the air and almost immediately evaporates. This cools the intake charge making it more dense.

This will supposedly help stop detonation (pinging), give better fuel consumption, and if tuned correctly the engine can possibly make more power due to being able to advance the timing more.

It should also clean carbon out of the combustion chamber.


Wawrick/Ray do either of you have a diagram or photo of your setups that could possibly be posted up here or know where i could find one?

Thanks for everyones help,
:cheers:
Dave
 
A search of this site for water injection will give a range of options / theories on the best or cheapest way to improve power or economy but a few basic items appear in most. Avoid siphoning effect and hydraulic lock with stop valve or non return valve. Found USA site that has kits, interesting for components used, would not be too dificult to source locally. :2cents:
http://www.snowperformance.net/
 
I have often thought of doing a water injection kit, but I am a little worried about possible long term engine damage. Has anyone run one long term, and did it have any effects on engine life?
 
This could sound rather strange but I made up a water injection system using an old plastic expansion bottle from a Renault 19. This has a hose going in at the top (about 1/2 inch) and a smaller hose at the bottom.

I connected a rubber hose from the old EGR outlet on the exhaust manifold to the 1/2 inch inlet at the top of the bottle and then ran the small outlet hose to a small needle and inserted this into the carby cover (I used a micro spray tap to adjust maximum flow).

As back pressure in the exhaust built up, it pushed more water out of the jet.

This worked quite well but I never really permanently installed it. I still have all the gear in the garage and will fit it properly one day. This is another way to solve the problem of increasing the water flow at high load (when the engine actually needs it) without resorting to pumps etc.

Please note : This is my own "lateral thinking" idea, and I have not seen it used before. I assume it would work well on any car provide it has sufficient back pressure.
 
EMC said:
umm... a newbie question here....

why do you want water in your fuel? isnt that usually a bad thing:question:

If you drive, or have driven, a carburettored car you may have noticed that it seems to run better on a cold, damp or foggy day. It's the same effect. It's a relatively small amount of water and it's not actually in the fuel, but in the air.

Warwick.
 
Dave said:
EMC,

Wawrick/Ray do either of you have a diagram or photo of your setups that could possibly be posted up here or know where i could find one?

Thanks for everyones help,
:cheers:
Dave

Dave,

I've got some of the bits somewhere. No photos of it fitted to a car. The last car I had it fitted to was sent to the government steel mill's crusher in Singapore in 1980. It was a Cortina from the '70s, so perhaps not a bad thing. I may even have some old brochures and literature for commercial units at the time. I'll send what I can find.
BTW, siphoning isn't possible when the vacuum air bleed control method is used.

Warwick.
 
I have been doing quite a lot of reseach on water injection lately for my MX5. I purchased most of the gear to do it myself, but have now changed my mind. For what it is worth, I am going to buy an Aquamist system from the UK. This is in a forced induction application though. http://www.aquamist.co.uk/

Cal.
 
Do you read Practical Classics? One of the writers recently fitted water injection to a turbo'd MX5.
 
Originally posted by mistareno
.....Please note : This is my own "lateral thinking" idea, and I have not seen it used before. I assume it would work well on any car provide it has sufficient back pressure.

Are you sure you didn't read the race report from the 1949 Australian Grand Prix?
 
Pugnut403 said:
Do you read Practical Classics? One of the writers recently fitted water injection to a turbo'd MX5.

No I don't. Do you have that issue?

Cal.
 
Originally posted by Stuey
I doubt whether they had exhaust gas recirculation emissions control setups in the '49 AGP!

True enough, but exhaust pressure was used to drive the water injection on the fastest car in the event... and too much of it caused its first pit stop (which I have on video somewhere here...).
 
Ray Bell said:
Are you sure you didn't read the race report from the 1949 Australian Grand Prix?

Well it's good to know I'm not the only person to have this idea. And as it made it through to a race engine, perhaps there is some merit in the idea.
By the way Ray in 1949 I was -27 years old, so no, I definately haven't read the race report :D .

BTW - Do you have any further info on how the car was setup??

Regards,

mistareno
 
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