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  • 3 weeks later...
  • 1 year later...

OK, thread raised from the dead.........I made 301.5rwkw today on a DD dyno.

I drove it around without a tune [that used the WMI] like forever...............it wasn't knocking and the car was making good power etc and I am a bloody busy bugger!!!

But I finally made the time and had it tuned. Run before tune made 270rwkw, then we kept adding timing and pulling fuel out until we had a good overall balance and got 300 on 16psi for the final run. I probably could have got more if I wanted to up the boost to say 18-20psi, but considering my motor is not built, I didn't think it was worth the risk.

I'll scan the plots and post soon.

Apologies to all who were waiting for this, I just couldn't get to it any sooner.

Well there is 10% more power, and I know that the curve is fatter in all area's, and seat of the arse says it definitely feels quicker all round, but that can be considered as being all pretty subjective - by some. Honestly making more power was a bonus, I really wanted fuel taken out [it was riched up to counter bad knock levels = the reason I went WMI]- so a better tune.

WMI is really just a band-aid for ineffective or insufficient cooling :/

Your fixing the symptom not the problem, but if it works it works.

I considered it but decided against it for the reasons above.

Happy hunting.:banana:

What problems have you encountered so far with the wmi system....if any?

I have a brand new kit tucked away........somewhere...hmmmm :unsure:

None, love it, works faultlessly.

And no its not for inefficient cooling alone, it is for too high a compression, low fuel octane, and an extra 30rwkw. Where I experienced knock had nothing to do with overheating. However having said that, the heat and burn rate inside the combustion chamber was likely not as controlled as it should have been. But when you are ramming more of everything into it [fuel, boost etc] then it is to be expected at some point. There are other solutions to solve it [E85, lower compression pistons /thicker gasket, smaller turbo etc], but I chose WMI

Dyno charts attached.

post-5748-0-54007800-1302833032_thumb.jpg

post-5748-0-15885800-1302833232_thumb.jpg

  • 8 months later...

Hey Trident,

Reviving your thread for some quick info

Im about to get my SRDE+T on the rollers and am considering a WMI kitup for myself, however I am thinking about it on a boost fed pre turbo arrangement with a very fine low pressure atomiser

Can you tell me the relative water use of your system? And can you tell me did you need to run dual maps to run with/without or was your tuner able to simple have a boost down area of the map and boost up area which needs the WMI?

I was hoping I could tune to the pre 12psi region without WMI and then the tuner goes hard from 12psi to whatever he can get using distilled water alone

It would be good to hear your thoughts having done it yourself :thumbsup:

my WMI setup turns on at 8 psi and goes to full flow at full boost, having a 9.5L water meth tank in the boot i find i only have to top it up once every 6 months - 1 year

though that will increase if you are the kind of person that gets right into it every time its driven.

the smaller tanks just check the level when you fill up or once a month if you arent a flat footed user (alternatively install a float switch into the tank to turn on a low level light on your dash when the tank gets down to 1/3-1/4 left)

if your WMI setup supports map based turn on/off, set it to come on at 12psi or a little before and then full at your target boost, that way the WMI isnt active below that point and there is no chance the tuner will go all out relying on the WMI to keep it safe below that point, alternatively if your ecu supports it, get the tuner to setup two iginition maps and have a switch between them, one tuned without the WMI and one with it, (you could even set the switch to turn the wmi system off and on as switched)

unfortunately my car is running a microtech, I am on the 'buy a house' budget now and cant afford to change it again

my thought is to have an airtight tank under bonnet with a barb on the top and a barb on the bottom

top barb has a check valve and a ball and spring like a turbo tech to regulate when boost can pressurize the tank, bottom barb runs direct to the atomiser which i will mount into the suction pipe on the turbo.

as the system hits target boost pressure the turbotech will open and push the water through the bottom side of the tank spraying its mist into the non boosted intake stream

thus the dual map idea isnt going to work too well unless i am manually switching... plus i dont think the microguess has dual map capability (i am surprised it can window in and out....)

good to know it doesnt consume it too quickly, I would probably end up with a 5 or 6L underbonnet tank if i was to go ahead with it and just want to know it will last atleast a week of heavy driving or atleast one full track day.

fair enough.. Im still in consideration stage at the moment.

the setup is a .86 28RS on an internally standard SR 10:1cr, im wondering now if the WMI will help me go beyond the compressors usual envelope or if it will just get me there more comfortably

being able to fill up anywhere and just keep going has been a priority to me in the past, it shouldnt change but i do have the power bug afterall.

Pre-compressor induction of the water spray is a different sort of science. And wait for the comments about wearing out impellers etc. It is apparent that you have to do it right, but it will work.

Sizing your nozzle correctly should yield a water:fuel ratio of somewhere around 15-20%

Some setups work better than others, and there are a couple of forums about dedicated to WI. Great pictures, and more than a few variations that will give you an idea of what you want.

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