j-rat.....just a thought....when u inject 120psi of liquid through a 100psi nozzel into a 26.7psi(12psi boost) enviroment.....would it be the same as if u inject it into 14.7psi enviroment?.....

on another note.....why would u want to replace gasoline with booze?..gas is ~2.40 where i live......while a gallon of alch u said is 9 bucks.....plus tax and its easier over 10 wouldnt it just be more economical to use more gas and less injection?...

and.....people dont convert to running purely alch because its specific energy(energy u get when u ignite the substance) isnt as high as gasoline......similarly.....gasoline's specific energy isnt as high diesel..thats why diesel engines are more efficient

ohh...and i got this thread saved......so keep going!!

 

i dont think actual ice crystals will land on the hot hot spinnin rotors spraying laughing gas just introduces more oxygen molecules into the chambers.....and i dont think steam cleaning has much to do with 2 stroke.....just keep in mind that alch and meyth can dilute the oil injected into the chamber to induce sealing

 

this thread is beautiful.

i think someone needs to try out hooking up a alcohol system, water injection, and also run a nitrous system.
hmmm...i wonder if it would make running a DRY nitrous system a better choice. makes sense actually...

 

ya, I didnt really think that there was much chance of damage from ice. but i am concerned about the water \ alc.. washing some lube off of the rotor housings. I couldnt really find any info on this. does anybody know anything about that?

 

Nope...not the same. You have to figure out the differential pressure across the nozzle.
120psi - 17psi boost = 103psi effective
103 (e)/100 rated =1.03
Square root of 1.03 = 1.0149

10GPH = 630.9 cc/min

630.9 * 1.0149 = 640.3 cc/min effective flow

One thing that clouds the issue even more is compared to testing with the engine off, the line pressure will be slightly higher when boost pressure at the nozzle is restricting flow.

Thats true, but race gas is also 5-8 bucks a gallon. If I filled my ENTIRE tank with race gas, then I am using all that octane wether or not I am boosting. With the Alchohol, I get the octane ONLY WHEN I NEED IT. Its like driving a car on 91 octane until I romp the pedal, then its like I have a tank of 110 octane!

Thats why you inject more. Yep, efficiency isnt as great, but alcohol is an abundant, renewable resource that can do the same thing gas does, but you just have to use more of it. So put a bigger tank in your car, and have fun!

 

I dont personally think that this is an issue. The injection system is still injecting oil, and the alcohol setup has lubricant added to the mixture. But beware, I cant provide any FACTUAL evidence that this is anymore or less safe.

 

Can you be able to use denatured alcohol to pre-mix with let's say... regular chevron fuel at the pump? Of course with the measurements of using about twice as much alcohol than fuel. For example if I mix 1 ounce of TCW-3 two cycle oil (to lube the apex seals a lot better) & 80% denatured alcohol and 20% 89 octane gas? Will that work? I have an S5 GTU non-turbo. Will it work on a n/a engine? I hear that it cools the combustion better and i'm looking on trying that out. Hawaii gets hot weather also. Correct me if i'm wrong, but the question is... will it work with any pump gas pre-mix?

 

You talking about that stuff from Home Depot or Lowe's?
Don't do it.
It has a LOT of crap in it.
A quick Google on "denatured alcohol" shows it's an ethanol derivative.
While SMALL quantities of ethanol is okay, running a an 80% mixture is going to kill your engine.
Now, DA isn't even pure ethanol, so that other crap is just going to clog up the fuel system and leave nasty deposits all over the insides of the engine.

Please...you're running an NA engine.
There's no reason to run 89 octane in it.
You should be running 87 and saving the few cents from running higher octanes.


-Ted

 

no need for water/meth/alcohol injection on your n/a anyways. Nowhere near as hot as a turbo. Nowhere near the detonation problem. No gains to be found. The gains come from being able to run higher boost.

 

From the MSDS (for those that know what an MSDS is):

PRODUCT: Ethyl alcohol (denatured)

SYNONYMS: Denatured ethanol

CHEMICAL FORMULA: C2H5OH

CHEMICAL ABSTRACT NO.: Mixture

PRODUCT CODE NO.: 12902

Section II - HAZARDOUS INGREDIENTS


COMPOSITION % CAS # TLV H
Ethyl alcohol 82.9 000064175 1000 ppm
Ethyl acetate 0.2 141-78-6 400 ppm
Methyl alcohol 16.4 000067561 200 ppm
Methyl ethyl ketone 0.5 000078933 200 ppm

 

I dunno I think you could get gains from a NA by running more advance. Of course you would have to have a standalone.

Read this...

http://www.aquamist.co.uk/dc/technic/technic.html

James

 

Normally aspirated car...

16. I have a normally aspirated car, would water injection help me to obtain more power?
No, in general. Unless you decided to increase the compression ratio, more advance ignition or run lower fuel grade than recommended by the manufacturer.

17. How do I advance the ignition timing?
Cars manufactured with knock sensor will automatically run more advance timing in the absence of knock. It is difficult to advance the timing on car without a knock sensor built-in.

18. My normally aspirated car suffers with sever detonation problem under heavy load such as towing, would water injection cure my detonation problem?
Yes, water injection will minimise the onset of detonation or even totally eliminates it, but you don't necessarily need to use the Aquamist system as high water pressure is not required, a ten-dollar washer pump and a water jet will work jet as well. Pay careful attention to prevent water from siphoning through the water pump during idle, a similar inline checkvalve will do the job.

19. Would water injection help to improve the economy of my normally aspirated car, ie more mpg?
Water injection will enable you to run more ignition advance so you can achieve MBT timing (Maximum brake torque) thus improve the efficiency of the engine, mpg will increase as a result but you need to carry a lot of water on board !

source: aquamist.co.uk

How much would you gain from advancing timing? Maybe I should have said "not much compared to a turbo" instead of "no gains." It certainly doesn't seem worth it for a n/a.

 

Before I start on this and before people get confused or upset, I would like to say this is nothing more then common conceptions being tossed around to help bettor understand the theories of the types of injection and how they work or help your car. Again me nor kontakt are using absolute values. Just place holders to simplify the process and understanding.

My previous arguments can be followed on pages 3, 4, 5 And kontakt can be followed on page 6.

Kontakt – On regards to post count 98 page 7: Not that my grammar / spelling has improved. More so on technical post such as this one, that can be very difficult to understand or follow with proper spelling / grammar let alone misspelled I been taking the extra effort to type in word. If they are basic 2 sentence posts I don’t normally bother.

I do not see any flaws in this theory of expressions. Basic brake down of if any current M is compressible then it will be compressed making room for W or another type of fluid, without sacrificing another type of fluid or air.

As we all understand that Av is our only value that is compressible and indeed is compressed under combustion.

Now I have to say when the W in this case is injected at the elbow before the TB but right next to the A temp sensor. I do not think the sensor will register the changing density of the air yet, thus causing the MAF or our charged air to be calculated at its charged temp from the flow rate provided by the AFM. With this in mind the air density is changing from the W beginning at or immediately after the TB and before the combustion chamber. Even more so the time the A has entered the motor before it has been cycled to the combustion the density is changing and expanding before the Av has had time to be trapped, this causing the total M of the A to be expanding.

The only way I see that W can be injected without sacrificing some component is to inject W right into combustion chamber. This of course being tunable on a car equipped with an EMS allowing the injection to occur anywhere. On a stock system I see my previous equations to be accurate.

Now by all means anyone is welcome to challenge this with me. I am not stating I am 100% correct. Science only proves previous consumptions incorrect.

On another note to J-rat. Alcohol being the combustible fuel that it is, do you feel or see it as safe to be injection before the TB? With an elevated risk of fire that it has being in front of the TB.

 

Not sure I understand this.. The spray is only when I am under boost, so how is it a fire hazard before the TB?

 

Sorry I do not have time to read the whole thread, but I have a few points to add.

Quite a bit of fuel is typically added to the combustion chamber for cooling purposes. While alcohol may do a decent job cooling the air instead of gas, it's still not as efficient as water. From www.waterinjection.info:

Also, another reason to add water is because it doesn't effect the amount of alcohol you can add, and vice versa. For instance, if you want to add water to air that's already at 100% RH, you can't without it dropping out. But you can inject all the methanol you want on top of the water.

If you're looking for a power increase from injection, I'd suggest nitromethane. It will give you much more power than alcohol or methanol. Ideally, I would choose a mixture of water, methanol, and nitromethane. You'd have the knock suppression and cooling characteristics of water, cooling and octane characteristics of meth, and the power increase of nitro. I would spray this either directly or pre-TB.

Another area worth looking into is pre-turbo injection. Even with a relatively poor setup the chance of impingement damage is relatively small. Ideally, one would use a very capable nozzle with a high-pressure or possibly heated system. I plan on using a system with a 50/50 meth/water mix. My plan is to place the nozzle very close to the impeller, aiming the spray directly at the shaft nut, which will help break up the water drops and send the water outwards, sending it through the compressor blades instead of at them.

The important thing to realize about that setup is that injecting prior to the turbo increases compressor efficiency and alters the adiabatic compression to achieve what most people refer to as "quasi-isothermal" compression. Almost no heat increase for the pressure increase. This seems to be most helpful for situations where someone is really pushing beyond the max of the turbo. The effect is that the islands of the compressor maps are shifted to the right.

 

Thanks a lot. Another thing though....? I was reading more reasearch towards other peoples experience on other forums such as fc3s.org and rx7city.com. Some of them say that it causes huge leaks on the injectors because of leaking through seals. It's a good cleaning solution in the combustion chamber, but also causes bad leaks. After I heard that, I was like.... forget it! Maybe upgrading the injectors would be fine, but you guys say it won't make a difference towards calming down the knock in the engine in my n/a so i'll take your word for it. Thanks guys!

 

wow, well there is something to definetly think about.
it's quite interesting how you say that it shifts the actual compressor map. this may help out people who are running near or past a turbocharger's peak efficiency range...

 

Not recommended...
This tends to kill compressor wheels.
More likely it'll induce small imbalanced, cause water droplets hitting an aluminum turbo compressor wheel spinning at 50k+ RPM's *will* cause pitting and damage.
Once out of balance, the turbo will eat its bearings in very short time.
This is why you almost never see this.


-Ted

 

I've seen numerous compressor wheels that used an extensive amount of water injection pre-turbo. The wear was no worse than what I've seen as typical for non-injected turbos. Furthermore, perhaps I didn't stress enough the importance of atomization? Right now, I don't believe a nozzle exists that could atomize water enough to work with a regular WI kit. In my opinion, that leaves two options: aim at the nut or Swirlflash.

 

Aquamist?


-Ted

 

https://www.rx7club.com/forum/showth...ater+Injection

http://www.teamfc3s.org/forum/showth...5&pagenumber=1

 

Nah, the point is that there is practically no knock in a n/a engine.

 

Hmm...I'm pretty sure I saw someone, maybe in the 3rd gen forum, do water injection right before the turbo for quite a while without any problems. I'll have to go look that up again.

 

Googled it, and from the responses, it seems that injection before the compressor damages blades..

 

I guess people don't want to believe me... :P


-Ted