Water/methanol injection

[bj70bc]

pre cups get hot no matter what they're in, that is their purpose, boost can actually help cool them down by introducing more cool air to the mix (at the same fuel load, tuned properly)
and water meth can help cool down the cups cylinders pistons egt further when under high load

 

[veiloctane]

considering this. I like the controller can do percentages over boost and or EGTs levels. Seems a bit more advanced than a simple on-off switch and offers more control.

 

[Dougal]

Just a note in ignition speed. Diesel is injected a significant time before TDC and starts to burn before then. It's peak pressure that is required to be close enough after TDC for good efficiency but not too soon to cause a big increase in combustion pressures.

Anything which adds to the burn speed will advance ignition speed and make the peak pressure happen earlier. Effectively advancing your injection timing.

If water/methanol supressed compression temps enough to not ignite water/meth then it couldn't ignite diesel either.

 

[KiwiDingo]

Yes, you can indeed get to a point it prevents the diesel from igniting. It's called the quench point and you only get to that point with huge amounts injected. From tests it's well over 1000cc/min before you get to it on a 4.2L TD engine. Those people who are running their setups for maximum potential like to find this quench point and then dial it back slightly for optimum injection performance. Most people never run anywhere near this point so it's hardly even mentioned or written about. I was running only 660cc/min and didn't bother going higher as my tank wasn't large enough and could easily use up my 50L tank an about an hour when programed for max injection.

 

[bj70bc]

Just a note in ignition speed. Diesel is injected a significant time before TDC and starts to burn before then. It's peak pressure that is required to be close enough after TDC for good efficiency but not too soon to cause a big increase in combustion pressures.

Anything which adds to the burn speed will advance ignition speed and make the peak pressure happen earlier. Effectively advancing your injection timing.

If water/methanol supressed compression temps enough to not ignite water/meth then it couldn't ignite diesel either.

Unless your meth/ water mixture is watery enough to quench said mixture from igniting itself while fumigated to the cylinder and being compressed to the autoignition point (as water does not auto-ignite),
then once a more volatile fuel is introduced ( diesel ) then combustion would occur (at a reduced temp) and still being able to take advantage of some meth fuel and the expansion of steam factor
no?

 

[Dougal]

Unless your meth/ water mixture is watery enough to quench said mixture from igniting itself while fumigated to the cylinder and being compressed to the autoignition point (as water does not auto-ignite),
then once a more volatile fuel is introduced ( diesel ) then combustion would occur (at a reduced temp) and still being able to take advantage of some meth fuel and the expansion of steam factor
no?

The steam effect is negative. It reduces temperature and pressure. That is why people have to add other fuel (methanol) or you go backwards.

If it wasn't you could run an engine by just injecting water instead of diesel. But everyone knows you can't.

 

[veiloctane]

Yes, you can indeed get to a point it prevents the diesel from igniting. It's called the quench point and you only get to that point with huge amounts injected. From tests it's well over 1000cc/min before you get to it on a 4.2L TD engine. Those people who are running their setups for maximum potential like to find this quench point and then dial it back slightly for optimum injection performance. Most people never run anywhere near this point so it's hardly even mentioned or written about. I was running only 660cc/min and didn't bother going higher as my tank wasn't large enough and could easily use up my 50L tank an about an hour when programed for max injection.

Thanks for mentioning the quenching point.

I was reading about this in the SP Diesel Stage 3 Manual and it mentioned dialing back when quenching is noticed.
what does quenching feel like does performance bog down like you put your foot down RPM and power feels sluggish and it's hard to move forward??

 

[KiwiDingo]

I can tell you now that 100% water injection most certainly improves things and most certainly isn't a step backwards like that guy above claims. Unsure why he keeps trying to make up facts about injection systems when he's never actually used or tested it? Soo many people around the world inject 100% water only and it works great. Mine worked so well I actually removed my big PDI front mount intercooler as it did nothing in comparison.

@veiloctane quench point just makes the engine stumble and kinda miss fire. It sounds quite similar to when you have cold start issues in winter when your fuel pump is too worn and running a bit retarded in timing or you removed the ACSD. Which kinda makes sense as that's exactly what water / meth injection does, it retards the start point of ignition.

 

[bj70bc]

I can tell you now that 100% water injection most certainly improves things and most certainly isn't a step backwards like that guy above claims. Unsure why he keeps trying to make up facts about injection systems when he's never actually used or tested it? Soo many people around the world inject 100% water only and it works great. Mine worked so well I actually removed my big PDI front mount intercooler as it did nothing in comparison.

@veiloctane quench point just makes the engine stumble and kinda miss fire. It sounds quite similar to when you have cold start issues in winter when your fuel pump is too worn and running a bit retarded in timing or you removed the ACSD. Which kinda makes sense as that's exactly what water / meth injection does, it retards the start point of ignition.

Thanks, there clearly is evidence that there is a benefit to just water injection in terms of steam expansion and reduced egt's in a diesel engine, the meth part does muddy the waters ( no pun intended) as even though it has a ignition rate that is slower than diesel, it is being introduced during the compression stroke where normally no fuel would be present and the compression ratio is such that it would ignite first as it is present first so i understand dougal's point on this effectively advancing timing and cylinder pressures too early especially in a idi (possibly). In a gas engine this is a different scenario of course( octane rating, detonation resistance, slowing flame front, advancing spark timing etc) so I think some people dont realize the difference.

 

[Dougal]

Thanks, there clearly is evidence that there is a benefit to just water injection in terms of steam expansion and reduced egt's in a diesel engine, the meth part does muddy the waters ( no pun intended) as even though it has a ignition rate that is slower than diesel, it is being introduced during the compression stroke where normally no fuel would be present and the compression ratio is such that it would ignite first as it is present first so i understand dougal's point on this effectively advancing timing and cylinder pressures too early especially in a idi (possibly). In a gas engine this is a different scenario of course( octane rating, detonation resistance, slowing flame front, advancing spark timing etc) so I think some people dont realize the difference.

Most people don't realise the point of an engine is to create heat and extract energy from that. Suppressing EGT with water makes your engine less efficient and your turbo even more so.
High EGT is a good thing right up to sustainable limits. That's about 650C continuous and even above 800C intermittent.

Squirting water into your engine to suppress EGT is completely counterproductive to efficiency and power. If you have an unsafe EGT or smoke problem then you have a tuning issue and that needs sorted.

Petrol/gasoline is very different. Water injection supresses detonation so you can run more advanced timing and more boost. None of that applies to diesels though.

 

[bj70bc]

so, understanding the effects of how diesel injection timing has an effect on egts, ie. advancing timing can reduce egts seen on an egt probe as more of the burn happens in the cylinder, vs. retarded timing increasing seen egt's as more of the fuel is still burning as it enters the exhaust manifold, i wonder if some of the reduction in egt's (using water meth) are happening because of the possible effective advancing of timing using water meth....
some of that has to be the water for sure though, especially if using just water.......

thought food
its a good debate anyhow
im going to experiment with it either way, it is just too interesting to me not to do it, very little meth will be going through it in any event, my egt's on the highway need a bit of cooling and im not wanting to turn down the fuel ( or up the boost), she just needs a wee little squirt me thinks
then i should be able to not have to get off the throttle on hills
aem v3 kit on the way.....

 

[Dougal]

so, understanding the effects of how diesel injection timing has an effect on egts, ie. advancing timing can reduce egts seen on an egt probe as more of the burn happens in the cylinder, vs. retarded timing increasing seen egt's as more of the fuel is still burning as it enters the exhaust manifold, i wonder if some of the reduction in egt's (using water meth) are happening because of the possible effective advancing of timing using water meth....
some of that has to be the water for sure though, especially if using just water.......

thought food
its a good debate anyhow
im going to experiment with it either way, it is just too interesting to me not to do it, very little meth will be going through it in any event, my egt's on the highway need a bit of cooling and im not wanting to turn down the fuel ( or up the boost), she just needs a wee little squirt me thinks
then i should be able to not have to get off the throttle on hills
aem v3 kit on the way.....

Advancing/Retarding timing affects EGT not so much by putting flame into the exhaust, but by having peak pressure occuring earlier so more or less heat is extracted from it by the expansion of the retreating piston.
Advance timing too far and you've got slightly more power but higher stress on everything and your turbo response suffers.
Retard timing too far and you've got hard starting, less power/torque, smoother, quieter, less stress on everything but turbo response gets way better.

How bad are your EGT on the highway and what's the boost numbers?

 

[bj70bc]

my timing is definitely retarded a bit...i moved it a mm or so when the turbo went on and had the injectors set to 1900-1950psi i believe
19-20 psi max ( intercooled), and can get it to 1200 1250 fairly easily on any kind of hill

 

[KiwiDingo]

i wonder if some of the reduction in egt's (using water meth) are happening because of the possible effective advancing of timing using water meth....
some of that has to be the water for sure though, especially if using just water.......

Most the reduction of EGT comes from the cooling of the intake air which in turn provides more dense air into cylinders which raises AFR causes EGT to drop. Works just like an intercooler only much better, when you inject enough you can get below ambient intake temps.

 

[veiloctane]

Most the reduction of EGT comes from the cooling of the intake air which in turn provides more dense air into cylinders which raises AFR causes EGT to drop. Works just like an intercooler only much better, when you inject enough you can get below ambient intake temps.

That's pretty cool so this "chemical intercooling" you probably could get by without a physical intercooler but i think your probably going to go thru more mix faster

 

[veiloctane]

View attachment 3357612
considering this. I like the controller can do percentages over boost and or EGTs levels. Seems a bit more advanced than a simple on-off switch and offers more control.

looks like it comes with a 4gph, 6gph, and 10gph nozzle to choose from.
since it only comes with 3 nozzles maybe start small 4GPH and 6GPH for the secondary. or maybe should order a even smaller nozzle maybe a 1.5GPH and a 2GPH to start with??

Includes:

300 PSI Extreme Environment UHO (Ultra High Output) Pump
Nylon Line
4AN Fittings
36 Inches High-pressure Boost Line
Digital Variable Mapping Controller
EGT Probe
Dual Nozzle Upgrade
Power Solenoid Upgrade
Bulkhead Fitting to Tap Into Stock Windshield Washer Fluid
2 Nozzle Holder/Check Valve Combo
3 Snow Performance Hypersonic™ Nozzles to cover a wide range of HP (4gph, 6gph, and 10gph nozzle to choose from)
Required Hardware Needed For Installation
Snow Performance Running S Decal
Snow Performance Injection boot (Rated to 65 PSI)
Comprehensive Instructions to Install on Any Turbo Diesel Vehicle

 

[Dougal]

my timing is definitely retarded a bit...i moved it a mm or so when the turbo went on and had the injectors set to 1900-1950psi i believe
19-20 psi max ( intercooled), and can get it to 1200 1250 fairly easily on any kind of hill

Those EGT are perfectly safe to run all day. I have run 750C (1380F) sustained for over 5 minutes at a time with no issues. I've also seen 900C in the past with no issues at all (I rebuilt the engine since for unrelated reasons).
My tdi PD engine has EGT sensors factory installed, it's been running north of 800C under sustained pulls for a decade with no issues.

The hotter your engine and turbo run the more efficient they run.

That's pretty cool so this "chemical intercooling" you probably could get by without a physical intercooler but i think your probably going to go thru more mix faster

No it can't and it's madness to pretend it can. You'll go through insane amounts of water and melt your engine when something goes wrong.

Ever stopped to ask why 100% of diesel engine makers love intercoolers and 0% of diesel engine makers squirt water into the intake?

 

[KiwiDingo]

That's pretty cool so this "chemical intercooling" you probably could get by without a physical intercooler but i think your probably going to go thru more mix faster

Yes you can but you need a large tank. The majority of people using chemical cooling only with no physical intercooler are mainly in motorsport applications like sled pulling, drag racing, rock crawlers etc. For a touring / overlander / every day driver application you'd be better off having both the intercooler and the injection system for the best of both worlds. If you already have the injection system you can also setup an additional nozzle to spray on the intercooler for even more cooling, a lot of rock crawlers do this as they aren't driving high speed to get the airflow through intercooler.

 

[veiloctane]

Those EGT are perfectly safe to run all day. I have run 750C (1380F) sustained for over 5 minutes at a time with no issues. I've also seen 900C in the past with no issues at all (I rebuilt the engine since for unrelated reasons).
My tdi PD engine has EGT sensors factory installed, it's been running north of 800C under sustained pulls for a decade with no issues.

The hotter your engine and turbo run the more efficient they run.



No it can't and it's madness to pretend it can. You'll go through insane amounts of water and melt your engine when something goes wrong.

Ever stopped to ask why 100% of diesel engine makers love intercoolers and 0% of diesel engine makers squirt water into the intake?

I can partly agree.

I can see hydrolocking being a issue but I think that Would take a lot of flow to do that. But not no where neir melting the engine.

It claims to be a “safe power adder” so I think it depends on how much you use and your tune.

Been reading lots of articles. Not much is said about the failures in these systems.

Water/Methanol Injection: How It Works And What It Does

Water/Methanol Injection is agreat way to boost power. QWhether it's the right way to do that in your truck is up to you.

www.dieselarmy.com

 

[bj70bc]

Those EGT are perfectly safe to run all day. I have run 750C (1380F) sustained for over 5 minutes at a time with no issues. I've also seen 900C in the past with no issues at all (I rebuilt the engine since for unrelated reasons).
My tdi PD engine has EGT sensors factory installed, it's been running north of 800C under sustained pulls for a decade with no issues.

The hotter your engine and turbo run the more efficient they run.



No it can't and it's madness to pretend it can. You'll go through insane amounts of water and melt your engine when something goes wrong.

Ever stopped to ask why 100% of diesel engine makers love intercoolers and 0% of diesel engine makers squirt water into the intake?

what engine? idi ? di? and are these newer engines with newer technology/ metallurgy piston design etc?
mine is an old tractor engine 3b-t....
i know that di can take more heat, and have heard people say their 1hdt xxx will take 1350-1400 (or more for short stints) without issue
I feel safe at 1150 continuously, 12-1250 for short pulls but start to worry about pre-cup, piston and head health much after that
some people seem to get all scared about 20 psi, but i feel the heat is the bad factor that needs to be mitigated

i appreciate the opinions offered from everyone