GMC Typhoon with WIS : Amount of water needed ?

[Roger G.]

A new customer came to us today and after he saw we are selling ERL Aquamist systems he complained about his system not doing a lot if any good. I checked his setting : System 1S with two 0.4 mm jets. He was told that this is the max water he should use on his engine. Also he should not mix more than 10% methanol to the water. Unfortunately this was told to him by another tuning shop on the Swiss market that sells ERL systems.

Engine specs :
- 4.3 liter turbo engine (still stock Garret)
- boost at 1.3 bars
- Air-Water-Air Intercooler
- Chip Tuning with external mapping of fuel and ignition
- Aquamist System 1s
- max tourque at 2620rpm

Now the Typhoons have pretty good intercooling what leads us to detonation control.

Questions :
- how much water should be injected to be successful in knock control ?
- methanol increases the octane rating but how much % methanol can be used ?
- the system currently uses two 0.4mm jets, would it be wise to use only one 0.8mm jet ?
- when the pump is activated at 0.8 bar of boost, rpm is only 2400 rpm. What happens if the Fuel/water ratio is more than 30% at this point ?

Thanks in advance
Roger

[Richard L]

I have had two encounters two syclones (both on our Gallery), one is running a few pounds over stock and the other ... about 800BHP.

First the 800BHP, 10s syclone runs twin-aquamist pump:
http://www.syclone.org/
http://www.aquamist.co.uk/forum/jets.JPG


Russel Bland runs sustem1s with two 0.5mm nozzles.
http://www.syclone.freeserve.co.uk/
http://www.aquamist.co.uk/forum/jet.JPG

They both get results in different ways. The Guy that runs 1.3bar boost should use at least two 0.6mm jets giving approximately 330cc/min or go for a twim pump system - up to 600cc/min, more with an accumulator [/img][/url]

[Roger G.]

Great links, thanks a lot, very helpful.

We were able to eliminate knock after 1.2 bars with two 0.5 mm and 50% methanol so far...of course he's gonna increase boost now :shock:

[Roger G.]

One more question arose today :

The system needs 3 bars of pressure differential to be able to atomize the water properly. With boost of 1.3 bars, the pump must provide 4.3 bars. But with two 0.6mm the pressure drops down to about 3.5 bars, right ?This may result in not fully atomized water as the pressure differential is only 2.2 bars. Will an accumulator be fine enough or is a second or a primer pump necessary ?

Thank, Roger

[Richard L]

Depending on the age of the aquamist pump, the pump produced from the last two years should sustain 6 bar of water pressure with two 0.6mm jets. Flow will be about 330cc/mim.

Make sure you have a good 13-14V supply to the pump.