Tripple'O G

Hey there.......

I've been told to complete my set-up I should be aiming to go for a fmic.........however
i've been told water injection is another way to go?

Who, what and why??

Gracias

Aztec Performance Ltd

iTrader: (234)

Whats the set-up?

Tripple'O G

VF34 Turbo, 650cc injectors, uprated fuel pump, GEMS ecu, full HKS decat,
anti lag/launch control, fuel pressure regulator, HKS air filter........

Adam M

you can go both ways.

some people see WI as a elastoplast covering up a problem.

I would use WI as a safety net but if you retard the ignition, it can give you more power than it costs you. If you do not alter the map, you can get a nice safety net built into your map.

Tripple'O G

So WI = More boost safer but costs a few HP?

Aztec Performance Ltd

iTrader: (234)

Overkill on the injectors and ECU imo.

I dont see WI as an alternative to good intercooling. STi8 TMIC would be up for the job.

I always wondered what happens when the water runs out and people have mapped it in?

Tripple'O G

So maybe a sti TMIC would be the way forward.........

Aztec Performance Ltd

iTrader: (234)

STi8 TMIC will comfortably handle anything the VF34 can produce.

Can the VF34 handle the anti-lag though?

Tripple'O G

Well thats the question........as long as you use it on occasion....

I'm going up to Mr Simpson (not homer) in march so I intend to turn it up.....blow it up.........and go for the 2.5......

jaytc2003

iTrader: (1)

if your thinking of the 2.5 further down the line then I would go with the fmic, as no doubt (theres a song there somewhere) you will end up modifying that as well!

Neilo

just bear in mine that the 2.5 isnt overly strong in terms of boost.

It seems that it will be fine with the same sort of sensible levels that the wrx 2.0 engine can take. i.e. 1.4 bar midrange and tail off to 1.2 at the top end...

Tripple'O G

at the moment i'm peaking at 1.3 bar....but it's popping and flaming all over the place......they guy before me had a "safe" map put in it and i'd be lucky if i'm making 280........hence why i'm looking forward to march...

so front mount looks like the best option in the long run.....any suggestions on make, type etc?

scoobysmiff

iTrader: (2)

speak to harvey,

charlesk

The main purpose of Water Injection is not to cool-down the charge temp, but to avoid detonation.
It does so by slowing down the combustion process and hence minimising the chance for detonation (in the same time it reduces combustion temperatures...). This is what will cause the loss of power as well, and hence the need to advance the ignition timing to compensate (some also go a step further and lean out the fuel mixture a bit as well).
Depending where you inject the water you might see a drop on the charge temp.
WI can help especially on cars with bad IC setups (my MR2 turbo with the side-mount IC was notorious for heat soaking the IC and the WI did help) but compared to a good IC setup, WI will not be as good/effective .
Another thing I would consider is the ability of the ecu to compensate for lack of water in case that you run out/pump doesn't work. (I do not know what GEMS can/can't do, so I'll say just ask whoever will be maping it...).
If it can't then mapping with WI on is strictly a no go.
With a good ecu, plenty of fuel (A/F ratio around 12:1-12.5:1) and carefull mapping there is no need for WI.
If it was my money I'd have a better IC (either STi8 of FMIC).
Hope this helps.
Charles

360ste

iTrader: (1)

A few months ago I got the chip in my GEMS upgraded by Steve Simpson as well as a setup on his 4x4 rolling road. Whilst looking round I saw that TEG Motorsport (where he is now based) sold Aquamist water Injection systems and asked his opinion. This was to go for the base model that runs off the boost as he does not like mapping with water injection as if it runs out of water or their is a blockage, it could be goodnight engine. Great if you want a 2.5 conversion. I have a FMIC on my bugeye kicking out 360 bhp on Steve's rollers, when he lifted the bonnet to disconnect everything he said "touch the pipe to the manifold" which I did. I think if i could have protected it from the heat from the engine any water sprayed on would have turned to ice. Have fun with what ever you do m8. Steve

DubaiNeil

Sorry 360ste, I'm a bit confused?

Did you have the Aquamist installed and hence the air inlet pipe is freezing cold, or you didn't and found you didn't need it?

I have been seriously considering Aquamist 1S for my MY02 WRX as the ambients temps here get ridiculous in the summer. I already have an APS FMIC, and am recording a charge air temp (measured via a probe in the inlet pipe to the throttle body) of no higher than 30C when moving, so I'm not sure if WI will add much value?

AndrewC

I think you mean advance the ignition there Adam.

So long as you use demineralised water and a decent filter then WI can be very reliable, also it is possible to monitor flow and hence detect blockages.

The benefits of WI are multifold, it cools the charge, reduces combustion temperature and hence egt, slows down the combustion process and cleans valves and ports as it goes, plus you can mix water and methanol (or other alcohols) to add both fuel and oxygen to generate even more power. Not only can you use more timing but you can also use a leaner AFR.

On the downside it adds complexity and if it goes wrong then you could be in det very quickly.

Andrew...

jameswrx

iTrader: (4)

Personally I'd go for the front mount intercooler.

I had a water injection setup on one of my old cossies, but I remember allways wondering about it.. is it working, is the jet gonna be spraying right, is it coming on at this boost etc.

I know they may well be realiable, but they certainly are not as reliable as a front mount Once you've got the intercooler on it's a case of set it up and not worry about it again.

plus, the price of the blumin front mounts at the mo, they are prob cheaper?

Nick Read

FMIC every time, of the two choices that is. IMHO water injection has limited uses. There is no practical downside to better intercooling. It will always be a benefit in any driving condition.

Water injection on the other hand is... well I hesitate to call it a bodge, because it has its uses...but let's just call it overkill on a road car. The descriptions above have pretty much got it, water injection IS a tool to lessen detonation - either to control it when it happens, or to stop it happening in the first place. But the fundamental thing is that IMHO it is the last line of defence if there is nothing else you can do e.g. you're quarter miling at Santa Pod, you're running 95 octane fuel cos the petrol station ran out of the good stuff, you've been in the staging lanes for half an hour already and it's 35 degrees C ambient, your whole engine bay and intercooler are warm enough to fry eggs on, you've got a high compression engine and your turbo is overboosting and you can't control it. Then use water injection to get you up the quarter safely and then go home and sort out all those other problems that will make detonation happen.

If you genuinely NEED water injection it's likely that you should first of all look at your intercooling, then look at your ECU mapping, then look at your fuelling provision and your actual fuel, then even a low compression rebuild if you're planning to use a lot of boost. Only after all that should you start worrying about water injection. IMHO of course.