I sold some mags to a pommy bloke who told me about a magazine he saw back in pomgolia.
The gist of it was, They got a window washer bottle and pump, heated up a pair of side citters with a torch and cut/melted the end of the rubber hose. Then drilled threee tiny holes in the flat end. This was routed into the intake of the turbo. It was actuated by a hobbs switch, so it only pumped once the boost had reached (whatever level it was) He said that in the article, by doing just this, they were able to advance the timing by (I can't remember the figure) but it also gave them quite a respectable horsepower gain too. (can't remember that number either)
Its a bit of a third hand story, but you get the idea. Another bloke I know swears by using boost pressure to force water/alcohol out of a sealed resovoir, and into the intake. The inportant thing would be to use tiny delivery holes, or having the delivery tube/nozzle aimed closely at the centre nut of the turbo wheel. Thus the significant conrtifugal force would aid the atomisation of the injected liquid. Some folk proclaim that liqud into the intake of a turbo will anihlate the compressor wheel. Yet drawthrough turbo's don't seem to do this?

Zoom did a water injection technical article over a couple of issues a while back.
i have it here somewhere in my stack. ill try to dig it up today.

good info guys, ive done quiet a bit of research on this now (thanking google). It apears that the closed chamber heads have a better squish value/properties and if used in conjunction with a lower (8-8.5:1) compression ratio would work well in boosted applications. Sharp edges and points also create hotspots in the head promoting detonation, smoothing these out will help and drop comp. ratio a fraction.

Heres a couple of links on water injection and detonation i found

http://autospeed.drive.com.au/A_107970/cms/article.html

http://www.superchargersonline.com/content.asp?id=104

Water injection seems to be coming up a bit..
The aquamist system was used widely by the WRC teams in the last few years until being baned this year!
A very good system but at about $1200.00, NOT cheap..
They will sell just the nozzles which are better than the finest of the agricultural (flojet) ones. They produce a very fine mist and are about $40 / jet.
The flojet type of pumps can be used. Use the 100 psi unit if the water is to be injected after the turbo. and should be just after the intercooler alowing the mist to fully vapourize before the maifold.
I`ll be using somthing along those lines when i get my engine finished. If anyone else sets up a system id love to here how they get on., Simon

(EDIT) sorry sikdatto, i looked at your links after posting, a link to aqua mist from there.

What about the vacuum advance mechanism? I have "heard" that the spring in the dizzy gets tired and can cause the mechanism to advance the timing too much.

Can anyone substantiate this vicious rumour?

Sunnydaze,
you dont have to worry about total advance. The springs dont control this , they control the rate of advance. (Which is still important) There are stops in the dizzy to control the amount of advance. the vac advance wont be working under boost. Some of the 2lts escorts had dual diaphram dizzys. maybe use a Vac canister off one of these and get boost retard. its worth 10 degrees on the escort.

Sicdatto1200- what type of carb and AFR meter are you using?

I in my ute (drawthrough, sc14 blower, d/d weber) I sometimes get pinging on transition from cruise to full throttle. the AFR meter clearly shows this to be a lean out problem-as the throttle plate opens the pump jets don't squirt enough extra fuel in.

people tend to report better results out of SU's than standard type carbies as they deal with velocity changes better.

WATER INJECTION-
somthing I am looking into so that I don't have to decomp.

Running a boost activated injection system on a drawthrough setup (with the water injection before the compressor) is conceptually flawed:

The manifold has achieved boost, the switch is triggered, water starts flowing into the carb/inlet manifold, through the compressor and finally reaches the inlet manifold....... how long after the initial signal? possibly only fractions of a second, but definatley a revolution or two after it was required.

to offset this I suppose you could set the switch a psi below where you need it.

Also, the guy at my local dyno shop assures me that running water through a turbo or supercharger will make atomisation worse, not better.

oh that sucks i just wrote a big post and it didnt work Its an injection setup using a haltech ecu, the afr is just a jaycar one, not the most accurate thing but still gives you a fair idea whats going on, im going to do a water injection system using $100 high pressure pump and correct jet, and using adjustable hobs switch and a solonoid etc, should be under $300 me thinks

You may be getting a few tings as you open the throttle grunter, because there is no draft door on the secondary barrell. With no air going through the secondary prior to actaution, there is no fuel imediately available at the booster venturi. Mine "blips" when I open the big hole. The factory carbs have a draft flap so that the draft of the motor gradually opens the door so that there is no "hole".

Quote:

Injection eh, you spoilt bast@rd!!

what water pump are you using and where is it from?

For my setup, all I need is a switch on the secondary throttle- Boost is directly proportional to throttle opening, so a simple throttle switch will do the job

I was thinking of using a stainless water filled fire extinguisher, about 1/3 full of water/meth. Rig some high pressure pipework to the inlet with an appropriate size jet and mechanical activation (throttle opening) then just add water/meth + 100psi from your local servo when you fill up.

the only problem is pressure drop/ flow changes as it discharges, and finding a stainless fire extinguisher in the right size.