So optimax boosts power what about cold air?

[lance]

I went out last night i was actually running on esso supper 97 ron and miss whiplash seemed quite a bit quicker than normal lighting up the tyres more easily than usual, ambiant tempreture was around 8-9 0c .
To me this slight drop in tempreture from say 12 -14 0c seems to have added extra boost torque and horses!

[The Flying Banana]

I went out last night i was actually running on esso supper 97 ron and miss whiplash seemed quite a bit quicker than normal lighting up the tyres more easily than usual, ambiant tempreture was around 8-9 0c .
To me this slight drop in tempreture from say 12 -14 0c seems to have added extra boost torque and horses!

Me too...over the past few days it has been around 9 10 oc up here and the car seems to be loving it, pulling stronger and more responsive

[Mrsmopp]

Me three!!! Pheiffer is a monster!! LOVE IT!! Bring on sub zero temps!

x

[lance]

It made me think , if only I could rig the aircon to the cold air feed in summer :sinner:

[Vikingxl]

I agree nearly wiped out an elise last night he floored it off a roundabout so i went for it and had to slam the brakes on as i closed the 20 foot gap instantly lets hope it stays cold for a while.

[BigJC]

4 degrees coming home tonight and it was loadsa fun!!!! What a cheap mod???
A move to Norway for more horses? hmmmmm....

[jp850R]

Me to, so much better now it gettin colder, they rekon -1 tonite, go out for a blast me thinks.

[craig]

ive just come back from scotland and while i was there i was getting overboost cos of the cold and now im back its not over boosting any more ,so if we get a very cold winter i might have to turn the mbc down a touch,

[splatt]

its all because the air is a little more dense at lower temperatures....:)

[weasel]

= more oxygen, best time of year to be driving... except for low sun.

[phil]

yeah more power but loads more wheelspin

Now getting it in 1st 2nd and most of 3rd!

Balance the boost,throttle lag and wheelspin is a nightmare, but fun

Damn Im off for new fron tyres again on staurday, I nearly got 11k out of these 2

[After_Shock]

As mentioned its a shame that cant get these sort of intake temps on the cars all the time!

[Engineer]

As mentioned its a shame that cant get these sort of intake temps on the cars all the time!
Water injection mate......................................loads of oxygen.........

[After_Shock]

Not that easy to set up that though is it?

[volvotuning]

Water injection mate......................................loads of oxygen.........

Water injection is not about oxygen for burning. It's about using water for cylinder cooling so that you don't have to use fuel enrichment for cylinder cooling. Pros and cons though.

Adam.

[Martinr]

Spent early part of the week up North and the combination of extra power and icy roads is not good :)

Can certainly feel the difference over the summer. Thank heavens for heated seats!

[John Ret.]

-3 here last night. Pretty good going.

[John Ret.]

Oh, and I love the orange "it's cold" LED which lights up when it's 2degrees or less.

Really handy.....

[mat562be]

I can remember trying my cousin's fruity Evo 6 RS in Norway one time, when it was about -18 or something. A large expanse of deserted, slightly frosted tarmac and about 340 bhp plus loads of dense air equalled much hilarity.... I'm laughing as I write this at the memories of it...

[Engineer]

Water injection is not about oxygen for burning. It's about using water for cylinder cooling so that you don't have to use fuel enrichment for cylinder cooling. Pros and cons though.

Adam.Thanks Adam well aware of that, but oxygen does not burn anyway it only aids burning hence the more of it the quicker you go. Simple chemistry.

[BlackBeast]

Thanks Adam well aware of that, but oxygen does not burn anyway it only aids burning hence the more of it the quicker you go. Simple chemistry.

Engineer, are you saying the more water you inject the quicker you go or the more oxygen thats present the quicker you go?

[Engineer]

Quote:
Originally Posted by volvotuning
Water injection is not about oxygen for burning. It's about using water for cylinder cooling so that you don't have to use fuel enrichment for cylinder cooling. Pros and cons though.

Adam.

Quote:
Originally Posted by BlackBeast
Engineer, are you saying the more water you inject the quicker you go or the more oxygen thats present the quicker you go?

To put this one to bed in laymen and not scientific terms will make for a shorter answer.

As previously mentioned the following occurs when you use water injection.

1. Water injection works to suppress engine knock in several ways. The water reduces the temperature of the compressed air. When the exhaust gases are expelled from the combustion chamber, the cylinder, piston, and valve surfaces are at a very high temperature. The water entering the cylinder with the compressed air will work to cool these surfaces and any hot spots which might exist.

But this also leads to us to the following advantage associated with water injection which may have been forgotten with the passage of time……………………………

2. As previously mentioned, the water serves to decrease the temperature of the charged air. Since water injection presents no additional flow restriction this reduction in temperature can only be accompanied by in increase in air density. So when the water cools the metal surfaces in the combustion chamber during the intake stroke it allows more air to enter the cylinder - effectively increasing the volumetric efficiency of the engine. This equates to more power, the same increase in air density you experience on a cold winters day.

Water injection is not a new idea it has been around for over 60 years by my reckoning and has been used to great effect in normally aspirated, supercharged and turbo engines in one form or another.

[volvotuning]

Quote:
Originally Posted by volvotuning
Water injection is not about oxygen for burning. It's about using water for cylinder cooling so that you don't have to use fuel enrichment for cylinder cooling. Pros and cons though.

Adam.

Quote:
Originally Posted by BlackBeast
Engineer, are you saying the more water you inject the quicker you go or the more oxygen thats present the quicker you go?

To put this one to bed in laymen and not scientific terms will make for a shorter answer.

As previously mentioned the following occurs when you use water injection.

1. Water injection works to suppress engine knock in several ways. The water reduces the temperature of the compressed air. When the exhaust gases are expelled from the combustion chamber, the cylinder, piston, and valve surfaces are at a very high temperature. The water entering the cylinder with the compressed air will work to cool these surfaces and any hot spots which might exist.

But this also leads to us to the following advantage associated with water injection which may have been forgotten with the passage of time……………………………

2. As previously mentioned, the water serves to decrease the temperature of the charged air. Since water injection presents no additional flow restriction this reduction in temperature can only be accompanied by in increase in air density. So when the water cools the metal surfaces in the combustion chamber during the intake stroke it allows more air to enter the cylinder - effectively increasing the volumetric efficiency of the engine. This equates to more power, the same increase in air density you experience on a cold winters day.

Water injection is not a new idea it has been around for over 60 years by my reckoning and has been used to great effect in normally aspirated, supercharged and turbo engines in one form or another.

Engineer,

I know it's been a around since the war, and I know it lowers intake temps. I thought (as mentioned above by someone else) that you were implying that the water itself provides the oxygen!! LOL

Anyway, to take your point further, there is one issue with using water injection on MAF based cars. That is that because water injection lowers the intake temps, it therefore increases air density. Now since the density increases, it is possible and highly likely that the air/fuel ratio will weaken because the MAF sensor has not taken into account the denser air made so by the water injection, and fueling at WOT is based on the MAF readings. You could argue that the cylinder cooling effects of the water injection will counter and resolve this problem at the same time by addressing the lean running automatically. However, without actually measuring this it would be guess work. That is why ideally, water injection should be mapped for.

Adam.

[Engineer]

Adam, glad we are now on the same track quick posts do lead to confusion sometimes. Good points with regard to the MAF and the adjustment of fuel injected when the combustion temperatures are lowered.

Therefore let’s take a quick look at ignition. The first thing that happens is a plasma cloud is formed by the arc consisting of super heated electron stripped atoms. As this cloud "burns" a ball of high energy particles is shot outward.

The highest energy particles are the hydrogen atoms - and they penetrate the charge about 5 times as far as the rest of the particles. As they lose energy and return to normal temps they begin to react chemically with any surrounding fuel and oxygen particles. The effectiveness of spark ignition is directly related to the availability of free hydrogen.

Volvo actually released some SAE papers documenting the use of cooled EGR to both reduce detonation and return to a stoic mixture under boost in the 15 psi range - while maintaining approximately the same power output. The important point here is that they actually reduced fuel and still get the same power output.

When you consider that EGR consists primarily of nitrogen, CO2, and water to the tune of about two gallons formed from each gallon of water used in the combustion process you might draw the conclusion that it was not "inert". Volvo peaked their tests at about 18% cooled EGR - which would work out to about 36% water injection and got about the same results under similar conditions that the early piston engine aircraft research obtained. Putting this aside for now lets take a closer look again at combustion.

During combustion water (H2O) is extremely active in the oxidation of the hydrocarbon. The predominate reaction is the following:

OH + H ==> H2O
H2O + O ==> H2O2
H2O2 ==> OH + OH
Loop to top and repeat.

The OH radical is the most effective at stripping hydrogen from the HC molecule in most ranges of combustion temperature.

Another predominate process is the HOO radical. It is more active at lower temperatures and is competitive with the H2O2 at higher temps.

OO + H ==> HOO
HOO + H ==> H2O2
H2O2 ==> OH + OH

This mechanism is very active at both stripping hydrogen from the HC and for getting O2 into usable combustion reactions.

Next consider the combustion of CO. Virtually no C ==> CO2. It’s a two step process. C+O ==> CO. CO virtually drops out of early mid combustion as the O
H reactions are significantly faster and effectively compete for the available oxygen.

Then consider that pure CO and pure O2 burns very slowly if at all. Virtually the only mechanism to complete the oxidization of CO ==> CO2 is the "water method".

CO + OH ==> CO2 + H
H + OH ==> H20
H2O + O ==> H2O2
H2O2 ==> OH + OH
Go to top and repeat.

This simple reaction accounts for 99% + of the conversion of CO to CO2. It is important in that fully two thirds of the energy of carbon combustion is released in the CO ==> CO2 process and that this process occurs slow and late in the combustion of the fuel.

Excess water can and does speed this conversion - by actively entering into the conversion process through the above mechanism.

The peak flame temperature is determined by three factors alone - the energy present and released, the total atomic mass, and the atomic ratio – commonly called CHON for Carbon, Hydrogen, Oxygen, and Nitrogen. The chemical reactions in combustion leading to peak temperature are supremely indifferent to pressure. The temperatures and rates of normal IC combustion are sufficient to cause most of the fuel and water present to be dissociated and enter into the flame.

As can be seen above, water is most definitely not only, not inert but is a very active and important player in the combustion of hydrocarbon fuel.

Therefore under certain conditions (normally turbo/supercharged ) water can replace fuel by up to about 50% and develop the same power output, or that the power output can be increased by up to 50% by the addition of water It is important however to note that these improvements did come at the upper end of the power range. Below that when cruising etc. the closed loop lambda sensor/s should correct any fuel irregularities.

Adam, I don’t have the facilities, but if you get the chance to run a custom map water injection system program it would be interesting to compare findings.

[splatt]

:wtf:

my cars faster than your car...

[volvotuning]

Adam, I don’t have the facilities, but if you get the chance to run a custom map water injection system program it would be interesting to compare findings.

It would indeed! Any volunteers?

Adam.

[fireclown]

:wtf:

my cars faster than your car...


Exactly.

[fireclown]

Adam, glad we are now on the same track quick posts do lead to confusion sometimes. Good points with regard to the MAF and the adjustment of fuel injected when the combustion temperatures are lowered.

Therefore let’s take a quick look at ignition. The first thing that happens is a plasma cloud is formed by the arc consisting of super heated electron stripped atoms. As this cloud "burns" a ball of high energy particles is shot outward.

The highest energy particles are the hydrogen atoms - and they penetrate the charge about 5 times as far as the rest of the particles. As they lose energy and return to normal temps they begin to react chemically with any surrounding fuel and oxygen particles. The effectiveness of spark ignition is directly related to the availability of free hydrogen.

Volvo actually released some SAE papers documenting the use of cooled EGR to both reduce detonation and return to a stoic mixture under boost in the 15 psi range - while maintaining approximately the same power output. The important point here is that they actually reduced fuel and still get the same power output.

When you consider that EGR consists primarily of nitrogen, CO2, and water to the tune of about two gallons formed from each gallon of water used in the combustion process you might draw the conclusion that it was not "inert". Volvo peaked their tests at about 18% cooled EGR - which would work out to about 36% water injection and got about the same results under similar conditions that the early piston engine aircraft research obtained. Putting this aside for now lets take a closer look again at combustion.

During combustion water (H2O) is extremely active in the oxidation of the hydrocarbon. The predominate reaction is the following:

OH + H ==> H2O
H2O + O ==> H2O2
H2O2 ==> OH + OH
Loop to top and repeat.

The OH radical is the most effective at stripping hydrogen from the HC molecule in most ranges of combustion temperature.

Another predominate process is the HOO radical. It is more active at lower temperatures and is competitive with the H2O2 at higher temps.

OO + H ==> HOO
HOO + H ==> H2O2
H2O2 ==> OH + OH

This mechanism is very active at both stripping hydrogen from the HC and for getting O2 into usable combustion reactions.

Next consider the combustion of CO. Virtually no C ==> CO2. It’s a two step process. C+O ==> CO. CO virtually drops out of early mid combustion as the O
H reactions are significantly faster and effectively compete for the available oxygen.

Then consider that pure CO and pure O2 burns very slowly if at all. Virtually the only mechanism to complete the oxidization of CO ==> CO2 is the "water method".

CO + OH ==> CO2 + H
H + OH ==> H20
H2O + O ==> H2O2
H2O2 ==> OH + OH
Go to top and repeat.

This simple reaction accounts for 99% + of the conversion of CO to CO2. It is important in that fully two thirds of the energy of carbon combustion is released in the CO ==> CO2 process and that this process occurs slow and late in the combustion of the fuel.

Excess water can and does speed this conversion - by actively entering into the conversion process through the above mechanism.

The peak flame temperature is determined by three factors alone - the energy present and released, the total atomic mass, and the atomic ratio – commonly called CHON for Carbon, Hydrogen, Oxygen, and Nitrogen. The chemical reactions in combustion leading to peak temperature are supremely indifferent to pressure. The temperatures and rates of normal IC combustion are sufficient to cause most of the fuel and water present to be dissociated and enter into the flame.

As can be seen above, water is most definitely not only, not inert but is a very active and important player in the combustion of hydrocarbon fuel.

Therefore under certain conditions (normally turbo/supercharged ) water can replace fuel by up to about 50% and develop the same power output, or that the power output can be increased by up to 50% by the addition of water It is important however to note that these improvements did come at the upper end of the power range. Below that when cruising etc. the closed loop lambda sensor/s should correct any fuel irregularities.

Adam, I don’t have the facilities, but if you get the chance to run a custom map water injection system program it would be interesting to compare findings.

yer but what about a diesel. running on veggymite.

[Engineer]

yer but what about a diesel. running on veggymite.RTFM.................................... ....................

[frodge]

so does this also mean that using a hho electrolysis setup would only make a difference high up the rev range.

[woz]

so does this also mean that using a hho electrolysis setup would only make a difference high up the rev range.

I wonder why? But then I dont know the details of the HHO electrolysis set up - can you provide a useful link? I would have thought it would provide the dissociated ions in freely available form for the processes at the beginning of the combustion cycle so therefore would make a difference across the rev range.

Love to get this thread going again.

i also seem to remember a quirky air filter arrangement being plugged in the 70's (doh!) which consisted of a wick filter soaked in water so that as the air was drawn throught the gauze wick it caused evaporation getting water vapour into the charge and evaporative cooling of the charge. Havent heard any more of this - sounds like it should work - perhaps I dreamt it.
An idea I would like to try is spraying water onto the foam panel air filter to seek the same effect. That would also be upstream of the MAF so the density change would have occurred before the MAF sensor thereby getting round Adams concern.

(However on that note, I am not convinced - if the MAF really does measure the mass of air, then it should not be upset by subsequent density and pressure changes - provide no air is lost or added, the mass remains the same) - any thoughts??

Cheers
Woz

[pangster]

Good luck trying to get an answer from Adam or Gary (Engineer) in this thread...

Adam has disappeared off the face of the planet lol! - due to certain escapades and Gary hardly every posts on here anymore..

[wegal]

Soaking Air filters in water... now i can help here. Put very very simply DONT !

When water enters a foam or paper filter the very first thing it does it expand the foam or paper, in doing so it virtually seals the air intake and the engine cant get any air to breath at all. Worse case senario is that the paper filter breaks up under the intake pressure ( soggy paper has no strength ) and then enters the air intake system, not ideal on a N/A engine bloody expensive on a turbo charged engine. ( chuck a bit of soggy cardboard type paper into the inlet side of a very hot and fast spinning turbo you can imagine the damage)

How do i know this ? Sadly by experience !!

I had an unfortunate incident when off roading one day when my air intake system sucked in water, the filter stopped the water entering the engine, but also stopped the engine breathing, result a massive loss of power half way through a very deep and long puddle. So naturally you floor it to try and get out the other side, it made it out the other side....... minus the turbo !!

[nathT5]

another track mod is to remove the n/s headlamp so the filter has no obstructions :wink:
not very legal on the road though unless its for "daylight use only" :eye-poppi

[pangster]

Soaking Air filters in water... now i can help here. Put very very simply DONT !

When water enters a foam or paper filter the very first thing it does it expand the foam or paper, in doing so it virtually seals the air intake and the engine cant get any air to breath at all. Worse case senario is that the paper filter breaks up under the intake pressure ( soggy paper has no strength ) and then enters the air intake system, not ideal on a N/A engine bloody expensive on a turbo charged engine. ( chuck a bit of soggy cardboard type paper into the inlet side of a very hot and fast spinning turbo you can imagine the damage)

How do i know this ? Sadly by experience !!

I had an unfortunate incident when off roading one day when my air intake system sucked in water, the filter stopped the water entering the engine, but also stopped the engine breathing, result a massive loss of power half way through a very deep and long puddle. So naturally you floor it to try and get out the other side, it made it out the other side....... minus the turbo !!

ouch!!! - sounds expensive!! :(

[pangster]

another track mod is to remove the n/s headlamp so the filter has no obstructions :wink:
not very legal on the road though unless its for "daylight use only" :eye-poppi

I can see the point on other cars - but ours has a nice direct cold air feed.. unless of course you are running an induction kit.. I know its quite big for Supra's and WRX's to run like this though.. :)

[woz]

Soaking Air filters in water... now i can help here. Put very very simply DONT !


Thanks Wegal. Just remembered the background while walking the dog today. It wasnt a watered wick it was a wick type carburettor, so it was petrol evaportation used to cool the charge.
Thats a subject I dont want to go bnear - and its a bit irrelbant to our cars anyway.

Excellent thought provoking topic though, so thanks.

Woz:>)

[LesRED850R]

its all because the air is a little more dense at lower temperatures....:)
Ahh , not entirely true as there is dry cold air as well..but mostly its damp and mostly its WET so the power cant be put down. I have had days when its 30 degrees Celsius and the HUMIDITY is high so the 850R loves it and torque is increased.I would like to know if others note that when you fuel up and drive off , is the power /torque increased as compared to B4 filling ? Is it cool fuel that helps ?? Its happened a lot and is noticeable so ???

[woz]

5 deg C less IAT is worth approx 1 HP.

(Oh yes and before anyone starts ripping this statement to bits it has come from two different sources - One was Moutune when I looked after an ex-works Ford Sierra and the other from a mate of mine who works for Bosch designing Engine Management systems)
mm thats interesting - is that 1 bhp PEAK or 1 bhp across the rev range? The difference bwteen summer and winter could be 25 deg C so about 5 bhp.

On our cars, 5 bhp at peak is a gnats - no one is going to notice, its the difference between having full or empty washer fluids.
But at low and mid range it could make a noticeable difference 5bhp in say 120bhp means a noticeable increase in thrust, and therefore driveability.

Accepted the quote is only a rule of thumb, but trying to put some context to it. Thanks for sharing.
Cheers.