water/alcohol injection for supercharger

[Well_Fans]

anyone tried fitting this to their monaro? came across this while searching ebay for magnacharger bits and pieces and it looks interesting but not something I've seen before

http://cgi.ebay.com/ebaymotors/METHAN

[jamiep]

Same kit i had fitted to my supra and i brought one for the monaro but ive not got round to fitting it.

[Gelf VXR]

I played around with WI with my previous turbo Astra. Main benifits are in cylinder cooling and detonation supression, you can run more boost, its like increasing the octane rating so that you can run more spark advance without knock, only applicable to FI applications. Can be used with SC and replace IC, or used in conjuction with IC, injecting prior to the SC marginally improves boost pressure, something to do with the water providing additional sealing between the rotors. Also cleans the combustion chamber of all deposits, steam cleaning.

Absolutely useless on my Astra as I was unable to program the ECU to allow higher boost pressure or advance the spark to take advantage of the benifits. You live and learn.

Unless you have it mapped for higher boost and spark you wont see much difference. If I get round to getting an SC, I would play around with WI again, now that I can program the ECU

Edited by Gelf VXR on Friday 27th June 13:05

[Gelf VXR]

Oh, I also have 50 liters of 50/50 water/methanol sat in the shed

[Well_Fans]

so if I'm running a 9psi magnacharger on my ls1 then fitting one of these kits could potentially make it safer for the engine by reducing risk of detonation? Already got the intercooler there to be fitted with the charger but if this could help even further it seems relatively cheap to add.

[anonymous-user]

Personally I wouldn't bother. If it's tuned right to run on normal unleaded you won't see detonation, however if you tune it for meth/spray and the system fails or runs out you will melt a piston.

[stevieturbo]

Well_Fans said:

so if I'm running a 9psi magnacharger on my ls1 then fitting one of these kits could potentially make it safer for the engine by reducing risk of detonation? Already got the intercooler there to be fitted with the charger but if this could help even further it seems relatively cheap to add.

Yes.

If you add water injection ( + meth if you want ) on its own, it will increase safety.
Adding it on its own, is unlikely it will produce any power gains. In fact, water alone, may reduce power. Water/meth...perhaps in small quantities it will gain a lot of safety, with no power loss.

If yo want the full benefits of such a system, then you need to re-tune accordingly, which again puts you back into a slight danger zone. And a big danger zone if the system fails.

[marcevo1]

adding too much wears valves and seats to pieces.

as stevie says - entering the danger zone relying on the squirt...

a 30bhp squirt on nitrous would be better to cool things down

[stevieturbo]

marcevo1 said:

adding too much wears valves and seats to pieces.

as stevie says - entering the danger zone relying on the squirt...

a 30bhp squirt on nitrous would be better to cool things down

What do you base the valve seat wear info on ? Ive never heard of it before ??

But true, nitrous would cool better. But its also slightly more expensive, and I dont think its inclined to help reduce detonation

[Gelf VXR]

stevieturbo said:

Adding it on its own, is unlikely it will produce any power gains. In fact, water alone, may reduce power.

WI may reduce power becasue it affects AFR, Octane rating and the flame front speed and thus optimum timing, the more injected the bigger the impact.

Example without WI

AFR @ WOT = 12 parts air to 1 part fuel

Examle now with WI

AFR @ WOT = 11 parts air to 0.85 part fuel and 0.15 water

Dependant on where the water is injected, before or after MAF.

Although with WI you might want to consider leaning the PE AFR which is normally richer than required for in cylinder cooling, robbing torque.

Tuning for WI is essestial

[GreenV8S]

Gelf VXR said:

Example without WI

AFR @ WOT = 12 parts air to 1 part fuel

Examle now with WI

AFR @ WOT = 11 parts air to 0.85 part fuel and 0.15 water

Do you think those figures are realistic? That would seem to be more water than normal, and you've also increased the fuel (and it looks richer than optimal to start with).

[jamiep]

Gelf VXR said:

Dependant on where the water is injected, before or after MAF.

You dont want the water going through the SC, it needs to be injected post charger.

[stevieturbo]

jamiep said:

Gelf VXR said:

Dependant on where the water is injected, before or after MAF.

You dont want the water going through the SC, it needs to be injected post charger.

A lot of people would disagree with that. Many, incl Mr Aquamist, would say you need to inject directly at the compressor wheel centre. This also applies to Rootes type blowers, where the liquid is used to keep the rotors themselves cooler. ( And turbos )

Also, water alone wont have a huge impact on AFR's Throw methanol in there, and AFR's will get richer.

I just prefer to inject after the blower, close to the TB. I wouldnt want to be injecting methanol onto the compressor wheel though. I doubt it would do any real harm, but being corrosive, Im sure it wont to the Alloy wheel any favours in the long term.

[Gas_Man]

Gelf VXR said:

Oh, I also have 50 liters of 50/50 water/methanol sat in the shed

Can you DRINK that?!

[Well_Fans]

so to sum this up - its a good idea as long as its tuned properly and doesnt fail when in use, if it does fail then it will ruin the engine that you're trying to protect by fitting it....hmm doesnt make it easy to decide does it. If I dont fit it and melt a piston then I'll wish I had and if I do fit it and it fails then I'd wish I hadnt....wish I'd never asked now, ignorance is bliss ...

[GreenV8S]

Aquamist comes with monitoring systems that give you a signal when everything's working correctly - the idea is that your ECU only goes into 'hooligan' mode when it sees a good signal, and by default it will run in a conservative mode.

[Gelf VXR]

GreenV8S said:

Gelf VXR said:

Example without WI

AFR @ WOT = 12 parts air to 1 part fuel

Examle now with WI

AFR @ WOT = 11 parts air to 0.85 part fuel and 0.15 water

Do you think those figures are realistic? That would seem to be more water than normal, and you've also increased the fuel (and it looks richer than optimal to start with).

This was just an example to explain how water displaces fuel in the ratio, what is normal depends on the set up and what you are trying to achieve, low amounts for in cylinder cooling, higher if your charge cooling to lower IAT's.

AFR for PE are something else all together, if you visit Innovate web site there you will find a paper that dispells the requirement as a myth that you have to run rich for cooling and run more spark, rather you you tune spark to the speed of the flame front of the optimum AFR.

Having not delved in to this, I'm sat on the fence

[Gelf VXR]

jamiep said:

Gelf VXR said:

Dependant on where the water is injected, before or after MAF.

You dont want the water going through the SC, it needs to be injected post charger.

Only quoting some of the benifits seen from users who injected before the SC from the aquamist forum.

I don't know why I mentioned injecting prior to the MAF??? not heard of ne one doing that doh


I was confused, i played around injecting just after MAF, just before the turbo, couldN'T aim directly centre as Stevie mentions, after the IC and at TB.

Edited by Gelf VXR on Saturday 28th June 14:44

[GreenV8S]

Gelf VXR said:

This was just an example to explain how water displaces fuel in the ratio, what is normal depends on the set up and what you are trying to achieve, low amounts for in cylinder cooling, higher if your charge cooling to lower IAT's.

That's how I thought it worked too, but unless I've misunderstood, in your example you added water and MORE fuel. The Aquamist site has links to an interesting article about the chemical processes that occur during combustion which seems to show that excess fuel is a relatively expensive (in terms of lost power) method of preventing detonation. The argument as I understand it is that excess fuel tends to prevent the second phase of combustion (from CO to CO2) which is the phase where most energy is released. Assuming that's accurate (I have no reason to suppose otherwise) then in cases where excess fuel is being added to suppress detonation, WI may give power benefits.

[Gelf VXR]

stevieturbo said:

Also, water alone wont have a huge impact on AFR's Throw methanol in there, and AFR's will get richer.

Mmm, I think I have to disagree, the methanol introduces more oxygen does it not? Thats means more fuel can be added as the mixture is lean

Edited by Gelf VXR on Saturday 28th June 15:41