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Water/Meth Injection vs Nothing - Results


jevansio
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Woke up today to a light frost so I thought I'd take the Supe to work to see if I could beat my 583rwhp score. Iphone showed 0 deg outside, it was dry & sunny so "perfect" conditions.

 

So once warmed up I did my first run 558rwhp, mmm down a bit, proceeded to do 3 more runs (recording the boost on the defi's to check I was seeing full boost to the redline - which I was), all 3 runs came in at or around 555rwhp.

 

So I noticed my WI was on (which Ryan had told me to turn off during tuning - but I turned back on the other day as I had just filled up the new plastic tank with 50/50 water/methanol).

 

I turned this off & did another run, 591rwhp :D, a personal best :D.

 

Just posting this as it's hard data & may be of use to someone, but for me proves that if your car isn't mapped to take the advantages of WI & you don't need it, the it's just sapping power (even if it is a methanol mix) :)

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Woke up today to a light frost so I thought I'd take the Supe to work to see if I could beat my 583rwhp score. Iphone showed 0 deg outside, it was dry & sunny so "perfect" conditions.

 

So once warmed up I did my first run 558rwhp, mmm down a bit, proceeded to do 3 more runs (recording the boost on the defi's to check I was seeing full boost to the redline - which I was), all 3 runs came in at or around 555rwhp.

 

So I noticed my WI was on (which Ryan had told me to turn off during tuning - but I turned back on the other day as I had just filled up the new plastic tank with 50/50 water/methanol).

 

I turned this off & did another run, 591rwhp :D, a personal best :D.

 

Just posting this as it's hard data & may be of use to someone, but for me proves that if your car isn't mapped to take the advantages of WI & you don't need it, the it's just sapping power (even if it is a methanol mix) :)

 

 

Be interesting for you to try it when its 23 to 24 deg outside..... :) I would only use this at very high boost on a hot day...

 

Im sure Chris W could give some input here?

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Be interesting for you to try it when its 23 to 24 deg outside..... :) I would only use this at very high boost on a hot day...

 

Im sure Chris W could give some input here?

Yeah, I thought that too (and will try it again in the summer & update this thread) :D

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What WI system are you using, what size jets and where are the placed, you may be injecting too much.

 

Do you have record of the difference in AFR with and without WI enabled.

Aquamist 1S, triggered at 10PSI, just changed to the .9mm jet (the one recommended for Supras, I do have the smaller one I used to run)

 

I don't bud but I can get it next time I'm logging with the laptop

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Yep too much water i would say, you are using the pressure operated system which basically gives you 100% of what the jet can pass all the time its on, you need it on a mappable HSV to take proper advantage.;)

 

Also what are you using to measure and log the BHP with Jay? as most of them are not that accurate.

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Yep too much water i would say, you are using the pressure operated system which basically gives you 100% of what the jet can pass all the time its on, you need it on a mappable HSV to take proper advantage.;)

 

Also what are you using to measure and log the BHP with Jay? as most of them are not that accurate.

Will try again with a smaller jet bud

 

It's the Racelogic Performance Box

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On SRR my car ran 555bhp without WI and with WI it ran 564bhp (Ryan increased the boost a bit - i think). Everything else on the car was exactly the same including the plugs.

 

This took place on 2 separate occasions (over a year apart) so weather, fuel, tyre pressures, etc could play a roll too.

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591 rwhp is mighty impressive Jay. :)

 

Outside temperature (like the 0°C you had) plays an important role on the power curve. Correct me if I'm wrong, but I thought that the main reason for WI was to be able to run safer higher boosts.

 

So I guess, putting WI on alone won't bring any benefit ... or am I wrong??

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OK, been out and swapped my other 0.5mm jet in (the smallest jet aquamist does).

 

Results weren't as conclusive,

 

I first did 2 runs with WI, it showed 535 & 537rwhp.

 

Then without WI I did 2 runs showing 555rwhp (it was upto around 13 deg ambient so I guess that's why it was down from the morning).

 

I then did another run with just to show it had gone back down & lo & behold it showed 556rwhp. I need to do some more tests I think now or even better get it on a dyno. The runs this evening felt a lot closer in terms of arse dyno too, compared to this morning where the you could feel it pull stronger without.

 

Either way I don't think even the smallest amount of water & meth that is possible to be injected with the 1S system is actually "adding" any performance to the car, again this is all IMHO.

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591 rwhp is mighty impressive Jay. :)

 

Outside temperature (like the 0°C you had) plays an important role on the power curve. Correct me if I'm wrong, but I thought that the main reason for WI was to be able to run safer higher boosts.

 

So I guess, putting WI on alone won't bring any benefit ... or am I wrong??

I dunno Luc, I've read all sorts on the benefits from cooling the charge before it enters the cylinder, to actual in cylinder cooling & the obvious det protection of using meth.

 

My EGT's didn't chage from the before & after (well not enough for me to notice on the gauge anyway)

 

I only ran these tests for my own benefit (as I hate taking for granted what people tell me). Things I know for sure are an 0.9mm jet is too big.

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I didn't think WI did add to the performance? I thought it only allowed an increase in boost safely? The fact the charge is cooler allows you to pack more of it in?

Dunno bud, I was always under the impression that injecting a small amount of water/meth would give a performance increase even without upping the boost (due to the cooling of the charge & the increased octane in the cylinder & cooler cylinder temps).

 

I'm going to dig out that large chunk of text that often gets pasted from the aquamist site & re-read it

 

EDIT this is one of the threads http://www.mkivsupra.net/vbb/showthread.php?t=96560&highlight=water+injection+benefits

 

PS I'm not a WI basher, I just like to put figures onto things to prove they do what they are supposed to do. I'm starting to wonder after re-reading that thread that the major benefits of the WI will start to show in the summer & the cooling properties aren't good enough in this already cool weather.

 

I also need to verify the RLPB to see if I can get a graph of bhp from it as if bhp is climbing when I reach the redline the results will vary depending on how soon I lift off :)

 

I will get the data I want though :D

Edited by jevansio (see edit history)
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Either way I don't think even the smallest amount of water & meth that is possible to be injected with the 1S system is actually "adding" any performance to the car

 

They way yours is setup its not supposed to add performance, unless you have mapped the car to take advantage of the added octane and cooling, ie more boost and ignition timing you will not see any gains.

 

When installed like most have them they are a safety net.

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