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How much does it drop egts on your setup?

They don't drop noticably at all with the new nozzle sizes. I still see 800-810 degrees if I hold it flat past 7000 rpm. This I suspect is due to the reduced volume compared to my last setup. There is perhaps 1-2 degrees more of advance in the ignition map with this setup, which is a nice safety buffer if I want to give it a hard time in 40 degree heat.

Yeah fair enough :)

I think I'll stay away from pre turbo on my car for now

I'd be to worried about water pooling as it would have to make a hard 90deg turn

Might have to try and get a temp reading though as the intake pipe sits directly above the turbos if it is hot enough to keep the water vaporized it may work

I understand the thermodynamics of what your trying to say but it doesn't make sense in reality. If water increased the dynamic comp then why don't you add it all the time? Surely you will gain hp everywhere? I'm not bagging water injection as a way of quenching chamber temps and slowing flame propagation rates but all the hype about it disassociating the hydrogen and oxygen and the water turns to steam which creates greater dynamic comp is a load of.

alot of high powered NA cars do run water meth for a hell of alot more time that you guys do on boost,

however I don't believe he said that it splits the water into Hydrogen and oxygen and it wont as you require a few other factors going on, like electrolysis.

Yet as for the increase in comp, it depends on where abouts in the cycle your talking, on the actual compression stroke you would prob see a decrease in compression as the water absorbs a hell of a lot of heat and cools the mixture making a lower pressure area, however then when you are on the combustion stroke, the water is heated way beyond the point it will remain as water and will become steam and at this stage you will have an increase in compression, im not 100% sure on if the net result will be an increase or decrease in compression overall and i really cant be arsed trying to work it out.

I understand the thermodynamics of what your trying to say but it doesn't make sense in reality. If water increased the dynamic comp then why don't you add it all the time? Surely you will gain hp everywhere? I'm not bagging water injection as a way of quenching chamber temps and slowing flame propagation rates but all the hype about it disassociating the hydrogen and oxygen and the water turns to steam which creates greater dynamic comp is a load of.

Water injected as a vapor is still an uncompressable liquid. This alone is the primary reason dynamic compression increases.

What happens with cylinder pressures when the water turns to steam during combustion doesn't relate to dynamic compression. H2o can not dissociate into base elements from pressure alone either. In the combustion chamber it just expands a lot due to the 950+ degree combustion temps.

Yes water increased all the time would increase power in theory. The problem is metering it correctly so you inject the correct amount per cylinder for ligher loads. If you consider that 425cc/min is correct for a 700hp 3lt 6 cylinder, the correct single nozzle size for the same engine making 45hp is 36cc, or 6cc cylinder. So you see for light loads the issue is getting accurate delivery to each cylinder without the nozzles blocking.

An alternative solution that I have read about for lean burn/economy tuning which might partially solves this issue is steam injection. Injecting as steam allows nozzle sizes to be larger. It also allows distribution to cylinders to be more easily achieved from a common injection point. Steam injection temps are high (say 150+ degrees), but still much less than combustion temps. Steam temps would also drop as they approach the engines intake valve and at the same time raise both the dynamic compression ratio and the effective octane rating of the fuel. This is a completely different concept to performance tuning with WMI though.

I remember seeing photos of a bloke with a supercharged 6 cyl falcon who mounted the nozzle in the snout of the blower and after 6 months had cut a slot in the impeller about 10mm long on each blade

This was back in the 90s so the kits were quite basic and just injected a jet of water rather than a mist

has anyone run pre-turbo for extended use ( eg couple of years) and noted any wear on comp wheel?

There is some good info on the aquamist forum about longevity of pre-turbo systems and wear on the impeller. Long story short was if you inject it correctly as a fine mist and have a good shutoff system there isn't an issue.

Water injected as a vapor is still an uncompressable liquid. This alone is the primary reason dynamic compression increases.

What happens with cylinder pressures when the water turns to steam during combustion doesn't relate to dynamic compression. H2o can not dissociate into base elements from pressure alone either. In the combustion chamber it just expands a lot due to the 950+ degree combustion temps.

Yes water increased all the time would increase power in theory. The problem is metering it correctly so you inject the correct amount per cylinder for ligher loads. If you consider that 425cc/min is correct for a 700hp 3lt 6 cylinder, the correct single nozzle size for the same engine making 45hp is 36cc, or 6cc cylinder. So you see for light loads the issue is getting accurate delivery to each cylinder without the nozzles blocking.

An alternative solution that I have read about for lean burn/economy tuning which might partially solves this issue is steam injection. Injecting as steam allows nozzle sizes to be larger. It also allows distribution to cylinders to be more easily achieved from a common injection point. Steam injection temps are high (say 150+ degrees), but still much less than combustion temps. Steam temps would also drop as they approach the engines intake valve and at the same time raise both the dynamic compression ratio and the effective octane rating of the fuel. This is a completely different concept to performance tuning with WMI though.

Your not listening - if you inject water in the most precise manner you will still lose hp power due to the effect that water has on lowing the flame progegation speed. And as for lean burn engines, slowing the flame front and adding another non combustable vapor is the exact opposite to what you want. I've worked with combustion engineers that have had petrol engine running as lean as lambda 2 and I've never heard of water or steam injection as a theory to help lean burn conditions. Do you realize that chamber temps decrease either side of stoic.

I have a direct injection VQ25 here with the high pressure mechanical fuel pump. I was going to ditch the heads and put the turbo ones on but you just gave me the idea of utilizing the injectors and pump for water injection. If I could get them to fire at different points in the combustion cycle it could have huge benefits, especially with high compression + ethanol...

Your not listening - if you inject water in the most precise manner you will still lose hp power due to the effect that water has on lowing the flame progegation speed. And as for lean burn engines, slowing the flame front and adding another non combustable vapor is the exact opposite to what you want. I've worked with combustion engineers that have had petrol engine running as lean as lambda 2 and I've never heard of water or steam injection as a theory to help lean burn conditions. Do you realize that chamber temps decrease either side of stoic.

Decreasing the flame speed is exactly what you want to do to reduce potential of detonation in high boosted engines, especially if guys are running these engines with tight quench and higher compression.

I spend a few hrs on the stagea today and mounted tank, and ran the lines under the car in convoluted tubing,(did a few other things at same time like running 8ga wire for hardwiring fuel pump)

still have to mount the solenoid/ wire it to igntion and drill and tap the intake pipe for the

injector and its done, maybe next weekend. I was thinking about running a 100cc jet with the stock turbo and see how much more i could get out of it with a bit of timing added for shit and giggles, whats a good

auto Rb25 neo make usually on 12psi-180-190rwkw?

cheers

darren

I have a direct injection VQ25 here with the high pressure mechanical fuel pump. I was going to ditch the heads and put the turbo ones on but you just gave me the idea of utilizing the injectors and pump for water injection. If I could get them to fire at different points in the combustion cycle it could have huge benefits, especially with high compression + ethanol...

Sorry mate fuel injecters wilcorrode/rust up,read it on other forums n was talking with a relative over easter bout this, he water injection on an old carby fed holden statesman. had a very basic setup think he had 5 smallish injectors into the carby into a spacer he had up had no injection at idle, then two would open up with the first two barrels when they opened, then the next 2 with the, 3rd an fourth barrells using the vacum (somehow) then the fith was on the front of the carby an opened under full throttle when there was no vacum powered buy a washer bottle pump. he never changed the timing didnt notice much performance but got a 50% improvement in fuel, went from getting 400km a tank to 600km a tank. but after a couple of months the nozzels corroded/rusted up. an he couldnt find any to handle water (that was quiet a few years ago)

also back in the 80's dad's cousin had water/meth injection on his car had great performance gains but if the car sat for a few weeks or a month the water/meth mix all went to jelly an clogged all the lines an the tank also had to be cleaned out..anyone had these problems?? maybe meth has improved over the years or the were running a different mix ratio.

as for getting power from water an old man from i think Dalby (se qld) did time for not paying tax on water used for fuel, tho thinking he may have bn using electrolisis, he could drive an old bus from dalby to cairns on 40L of fuel..about 2000km!!...tight arse government lol

wish i'd descovered how good water/meth injection a cpl months ago before i spent money on cams to get more power while sacrificing drivability...but its got a nice idle lol

Sorry mate fuel injecters wilcorrode/rust up,read it on other forums n was talking with a relative over easter bout this, he water injection on an old carby fed holden statesman. had a very basic setup think he had 5 smallish injectors into the carby into a spacer he had up had no injection at idle, then two would open up with the first two barrels when they opened, then the next 2 with the, 3rd an fourth barrells using the vacum (somehow) then the fith was on the front of the carby an opened under full throttle when there was no vacum powered buy a washer bottle pump. he never changed the timing didnt notice much performance but got a 50% improvement in fuel, went from getting 400km a tank to 600km a tank. but after a couple of months the nozzels corroded/rusted up. an he couldnt find any to handle water (that was quiet a few years ago)

I knew the pump and injectors wouldn't last long with water alone, I was contemplating flushing the system with WD40 or mixing a little water soluble oil in perhaps. I'm just interested to see what effect direct injecting the water at different points in the cycle would have.

im seriously considering a WMI kit as safety measure and hopefuly bring turbos on sooer,

how would the SNOW stage 2 performance water methanol kit go in an R32 GTR?

is there another kit more suited to these cars?

this may be a stupid question, but where do you purchase methanol from?

Would still be worth it as a safety measure. Even injecting just distilled water

Just curious as to where one would mount the nozzle on a gtr? On the plenum? Or on the intercooler hard pipe joining to the plenum (that's if you have an alloy pipe there and not the stock rubber one)

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