› Forums › Repairs & Technical › Repairs & Technical for Golf & Passat cars › MK2 GOLF SPEEDO WRONG (now…water injection)
hmm ok good food for thought. I’ve done some stuff with little piezo foggers before, I wonder if it could be made in sufficient volume to work on a car.
Once I’ve got the syncro together I’ll have to have a play with a spare inlet pipe and see if we can get anything going in that direction. I guess whatever atomisation method it uses it’ll need the same basic pipework to feed it liquid.
re alcohol – so it doesn’t have to be directly methanol then does it? I guess meths is the easiest to get hold of. Could you perhaps mix octane booster with water and mist that in there?
tbh startig with water is probably a good idea and then complicate it later…
pritty much,
alcohol dosent have to be methanol, and it dosent have to be a strong mix ether meths is the easyest and the cheepest to get hold of in small volumes, not sure if octane booster would mix with water. but water on its own has same effect as octane booster ( by lowering the pre combustion in cylinder tempriture ), the alcohol will boost the octane iirc methanol is the eqivalent to 112 octane
ok whilst I don’t like the idea of raw meth for all the reasons mentioned earlier it does look like the thing most likely to actually be what we want it to be… octane booster. I guess if it’s only small quantities and it’s stored as mixed with water there should be no problem?
Where would I get methanol on a regular basis? Race shop at santa pod I guess? Do I need any special paperwork in order for someone to sell me it (or to keep it at the house)?
Btw EDDY I’m apologies re hijacking this thread, but it looks like you “sparked” some interesting ideas…
ebay there are compnays advertiseing there that will sell you 99.95% in barrels 25’s or 205’s . your makeing bio diesel arnt you
flamablity wise think spiritsthere ethanol whitch is pritty much the same except it’s not toxic like methanol if drunk. 50 % will light but it only just burns really. 40% needs a fair bit of perswation to light and really isn’t that keen on burning.
you don’t need spectial paperwork to buy methanol transporting 205 ltr barrels is proably a bit iffy but 25’s arnt a problem imo. storage is the iffy one, i would not store 205 ltrs of methanol in my garage or even at home as if the worst happend it’s rather a lot of flamable liquid and the insurance company would not be inpressed i think std houshold poliy allows you store upto 10 lts of petrol in cans. id get 25 ltrs and mix it down imediatly and keep it in the shed away from anythign that may try and light it then it can be considerd safe imo.
Howdy,
Word of warning to water injection.
I had a simple water injection kit on a old polo in the 1990s which worked good, once i got 70mpg out of her on a long run[].
But after wanting more performane i put 50% meths 50% water in the tank and put too much of the mix in at high revs.
The compression droped soon after as i think i had washed the cylinder bores.[]
I recon with higher % of water meth mix i would change the engine oil to a castor based oil as used for methanol runing engines.
Change the oil often and keep an eye on oil levels!
Ps, anyone got a dash for a syncro ?
keep the syncros going, i am starting to like mine a lot.
Here is a suitable oil, the price is horrendous though!
Castrol M SAE 50 is a special lubricant formulated from first pressing castor oil , free from contamination and developed for use as lubricant for model aircraft engines using methanol fuel . 4 litres bottle .
Also useful as lubricant for dragracing .
http://cgi.ebay.de/Castrol-M-Rizinusoel-fuer-Nitromethan-Methanol_W0QQitemZ310138569001
if you stick to injecting water at 25% the rate of petrol your safe, or about 12.5% rate of methanol.
adding a littel helps but once you start adding a lot problems can occur the 16v is a safe enigne to experiment on as it dose tend to go lean up top so will burn all the fuel you add and not leave unburn fuel to trash the bores.
iirc the KR’s injectors flow about 220cc/m when there going flat out. 2.0 16v’s run out of fuel at about 170bhp. so rough guestimation say . if we say a normal heasthy Kr is going to make about 150 bhp and it’ll be getting 195 cc/min per
with 4 cyl enignes working out how much water is easy it’s equal to the flow of one injector. when adding lots of alcohol in larger volumes more thought is needed.
say we take a 2.0 16v with some tweeks that wants to make 200 bhp but the k jet is giveing up at 170, need to make up 30 bhp worth of fuel but for the same volume of air you use roughly twice the volume of meth. so say 220 cc/ min of petrol is makeing 170 bhp thats roughly 1.3cc/min per bhp double that for meth so it’s wanting 2.6 cc/min of meth per horse power
2.6 cc/min hp for 30 hp = 78cc min ( that can be rounded up to 80 to make life easy as it’s all a bit ish anyway ) now with methanol going into the system not as much water is need to hold off detonation and to be on the safe side if your worried about bore washing leave the water injection jet the same size and just adjust the concentation of alcohol in the water it’s injecting.
so you have 4 injectors fireing 220cc min of petrol and a nossel spraying 220 cc of water and meth mix at 36% should see you meeting the fueling needs for 200bhp.
sugest working out your own numbers and verifying the size of the injectors tho as these numbers are very rough gestimation but should give idea of what has to do
Just a thought, could you use a 5th injector in the inlet manifold for the water injection?
ok, it probably wouldn’t last forever with the water going through it instead of petrol, but it should have a reasonable length of life, shouldn’t it?
You could possibly use a small dedicated pump to get the needed 3 bar pressure.
it wouldd give ecelent atomisation and control and it would make for a cute system, very controlable a simpel PWM drive circuit that chould take it’s input from a TPS.
dont quite know what a fuel injector would think of water but there is one way to find out.
quote:
Originally posted by dannypdont quite know what a fuel injector would think of water but there is one way to find out.
I was thinking of using old and or disgarded fuel injectors (scrappy racer style) as as long as it atomised the water I dont think you very worried about the spray pattern etc, or are you? []
old injectors are in plentyfull supply and so if they give up after a reasonable time it’s not going to matter it’s not like you have to buy them ether
could one add something to the water to prevent corrosion? e.g. like they put in coolant?