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Old 19-03-2005, 02:41 PM
Wet1 Wet1 is offline
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Default Injecting high concentrations of alky?

A couple of us have started talking about this topic in another thread, to preserve the content of the other thread I'd like to continue the topic here.

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Old 19-03-2005, 02:46 PM
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Originally Posted by Wet1
I've noticed on this site there seems to be a heavy useage of water or water/alky mixes... many, if not most, in the US are now shooting straight methanol (or ethanol if their pump won't handle methanol) with fantastic results.

I my intent is not to start a feud on which is better (this is not the place), just wondering why you want to go through all the trouble of making this work with such a heavy concentration of water???
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Old 19-03-2005, 02:47 PM
Wet1 Wet1 is offline
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Originally Posted by hotrod
I can't speak for Richard, but since the 50/50 mix of water and methanol is a benchmark for WI systems it is useful to determine how or if you can run more complex mixtures while still maintaining the 50% water.

It also is simply an economic issue. The water is essentially free and available everywhere.

There is a lot to be said for alcohol hybrid fuel systems ( which is what an alcohol injection system is ) but I feel there is still a lot of performance still on the table with simple water injection.

It was demonstrated 50-60 years ago that with an optimized tune, you can double engine power output with just water and methanol. Running straight methanol on the other hand is only able to deliver about a 15% increase in power before you get back into detonation / pre-ignition territory. The problem is, that current engine managment systems are not very friendly to the type of changes you need to make to get to the high power outputs with WI and still provide a fail safe tune if the WI fails.

Larry
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Old 19-03-2005, 02:50 PM
Wet1 Wet1 is offline
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Originally Posted by Wet1
Thank you for replying Larry. I am very impressed with your knowledge and the contributions you make on this site, I hold your opinions in high regard. What do you do for a living, chemistry? Are you in the US? Are you in the water injection business, or is this just a hobby?

On this site the 50/50 mix does appear to be the benchmark, but most other places seem to recommend straight alky over water mixes. I do not know which is better. I use W10/M90 mix because I need the fuel from the alky and don't know if water is better or not so I throw in the 10% water. I often wonder if the only reason leading authorities on the subject say to use water is only because their kits can't handle straight methanol so they don't have much experience with it or discredit it for this reason. How have you come to the conclusion that a 50/50 mix it ideal? I know there were several studies on water injection many many years ago, but I question if a fair amount of recent research as been done on methanol, water, or mixes for water/alky injection in todays FI engines. Again, I respect you opinion and would love to hear further input.

While I agree water is cheaper, I don't think cost is much of an issue for most users. Methanol is < $4 / gallon and as you know a gallon goes a long way.
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Old 19-03-2005, 02:51 PM
Wet1 Wet1 is offline
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Quote:
Originally Posted by Richard L
Wet1,

Welcome to the board. I am pleased to have someone who is experienced with pure alochol injection.

Aquamist has always been designed to run 100% water because rally cars are not allow to run with any additives - our fist six years of production were for Rally cars only and not to the public. From 1997 - we entered the aftermarket.

I must admit that I am not familiar with the use of alcohol except for anti-freezing purposes. It is just as easy to convert the aquamist pump to pump alcohol.

I can see another problem with the aquamist pump when used with alcohol- I visited some boards, the amount of alcohol used is just incredible - a 2-litre per minute gasoline flow is laced with one litre of alcohol !

I have no objection of people wants to run everything pig rich for the sake of cooling the engine and stop it from blowing up - but what a waste! I am not "Green" nor concerned about "Global Warming", just try to design a product that is sensible. The thought of ramping up the alcohol flow until the engine bogs down and then ease it back a little - I cannot accept this method as a very scientific way to tune a car.

Part of the reason for such large delievery is propably due to methanol has only 50% of the latent heat of water by 'mass' and 40% by volume. 300cc/min water = 750cc/min of methanol, or 940cc/min of ethanol. I think isopropyl is even higher.

I would like to learn more about alcohol injection, perhaps you can help me designing a proper system for alky users.

The reason given was only my own opinion and not the board's.
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Old 19-03-2005, 02:55 PM
Wet1 Wet1 is offline
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Quote:
Originally Posted by hotrod
wet1:

Quote:
Thank you for replying Larry. I am very impressed with your knowledge and the contributions you make on this site, I hold your opinions in high regard. What do you do for a living, chemistry? Are you in the US? Are you in the water injection business, or is this just a hobby?
Thanks for the kind words, --- I currently work in the computer industry, but have done lots of other things over the years. Mostly I'm just really curious and have an engineers mentality. (started out to become an mechanical engineer many years ago but got side tracked by other events in life.)

Quote:
How have you come to the conclusion that a 50/50 mix it ideal?
Mostly based on the studies during development of ADI for WWII military aircraft. They were trying every combination they could think of -- it was litterally a life or death problem to solve, as pilots lives depended on very small power advantages under combat emergency power. After exhaustive tests they concluded the 50/50 mix was the most effective. It is still used to this day in unlimited air races and hydroplane races. Thats good enough for me !!

If I ever get anywhere near the limits of a 50/50 mix (MW50) which is nearly a doubling of max torque, then I might investigate other possibilities.

The folks who are using straight alcohol injection are actually doing something different than normal WI. They are getting some detonation protection but they are mostly creating a hybrid fuel system that under max power it approaches being a pure alcohol fueled engine. As I mentioned above, with no water added to the mix, you are limited to about a 15% power increase just switching to alcohol vs gasoline. That is a very impressive number for a 400 -600 hp engine, and is more than most folks need.

Larry
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Old 19-03-2005, 02:57 PM
Wet1 Wet1 is offline
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Originally Posted by Wet1
Richard,
Thank you for the warm welcome. Interesting site, I assume it is yours (Aquamist). Love the theory and application of WI/AI and was looking for more info online while also looking for yet another alky injection system for my latest project (a SC Z06 Corvette). Looking at your system, I have decided to isn't for me for a couple of reasons, but your forum is very much of interest to me because the world and wealth of knowledge on this topic is relatively small.

As you mentioned, some people are shooting very high volumes of methanol. The more you shoot, the more fuel you have to pull out from the main fuel system. It's no secret that you can make more power on methanol than on gas. The more alky that is injected the more you're converting the engine towards a methanol fuel source (more boost and timing can be added). Most people are not adding anywhere near the volumes you mentioned. I find myself using about 80% pump gas and 20% alky by volume under boost... but keep in mind that you need to add about three times as much methanol as you would gas to maintain the proper A/F ratio. Although I'm injecting 20% alky, it only accounts for about 7% of my fuel source. In other words, if I'm injecting 20% of my overall fuel in the form of methanol, I'd need to reduce the gas required from 100% back to around 93% to keep the proper A/F ratio. So while at first glance it looks like you'd be running "pig rich", you actually are not.

You can use the basic method of tuning you described (ramping up the alcohol flow until the engine bogs down and then ease it back a little) and it will work to get a safe tune with alky or water, but it's far from optimal. I use EGT, KR, and A/F ratio together to nail down the tuning... works great.

If I were you, I would strongly consider make a kit that is compatible with straight methanol so your customers have the option to play with alky. IMO alky offers many of the same attributes as water, but also adds some bonuses (like additional fuel, drastically lower IAT's, increased octane...) You can add WI to a FI engine and it will control detonation quite well, but when you shoot straight methanol you not only control detonation, but you also add power with no other changes.

Designing a system for use with alky is very simple... just make sure everything is corrosion proof and rugged. I don't think your pump will do the job for a high volume alky system. From my experience you need a pump that will handle high volumes, is pressure adjustable, and can't have metal parts in contact with the alky. In the US we have found this pump to be cheap, very rugged, capable of very high volumes, and will do 60 - 180+ psi...
http://www.northerntool.com/webapp/w...&issearch=2687
Add in some SS braided lines, good fittings, and an excellent boost referenced controller and you have magic!


Scot
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Old 19-03-2005, 02:59 PM
Wet1 Wet1 is offline
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Quote:
Originally Posted by Richard L
Wet 1,

Quote:
Originally Posted by Wet1
Richard,
Thank you for the warm welcome. Interesting site, I assume it is yours (Aquamist). Love the theory and application of WI/AI and was looking for more info online while also looking for yet another alky injection system for my latest project (a SC Z06 Corvette). Looking at your system, I have decided to isn't for me for a couple of reasons, but your forum is very much of interest to me because the world and wealth of knowledge on this topic is relatively small.

As you mentioned, some people are shooting very high volumes of methanol. The more you shoot, the more fuel you have to pull out from the main fuel system. It's no secret that you can make more power on methanol than on gas. The more alky that is injected the more you're converting the engine towards a methanol fuel source (more boost and timing can be added). Most people are not adding anywhere near the volumes you mentioned. I find myself using about 80% pump gas and 20% alky by volume under boost... but keep in mind that you need to add about three times as much methanol as you would gas to maintain the proper A/F ratio. Although I'm injecting 20% alky, it only accounts for about 7% of my fuel source. In other words, if I'm injecting 20% of my overall fuel in the form of methanol, I'd need to reduce the gas required from 100% back to around 93% to keep the proper A/F ratio. So while at first glance it looks like you'd be running "pig rich", you actually are not.

You can use the basic method of tuning you described (ramping up the alcohol flow until the engine bogs down and then ease it back a little) and it will work to get a safe tune with alky or water, but it's far from optimal. I use EGT, KR, and A/F ratio together to nail down the tuning... works great.

If I were you, I would strongly consider make a kit that is compatible with straight methanol so your customers have the option to play with alky. IMO alky offers many of the same attributes as water, but also adds some bonuses (like additional fuel, drastically lower IAT's, increased octane...) You can add WI to a FI engine and it will control detonation quite well, but when you shoot straight methanol you not only control detonation, but you also add power with no other changes.

Designing a system for use with alky is very simple... just make sure everything is corrosion proof and rugged. I don't think your pump will do the job for a high volume alky system. From my experience you need a pump that will handle high volumes, is pressure adjustable, and can't have metal parts in contact with the alky. In the US we have found this pump to be cheap, very rugged, capable of very high volumes, and will do 60 - 180+ psi...
http://www.northerntool.com/webapp/w...&issearch=2687
Add in some SS braided lines, good fittings, and an excellent boost referenced controller and you have magic!

Scot
Thanks for the link, the shurflo pump is ideal for the application as many alky-injection manufacturer uses it, in fact all of them except SMC - pure alky injection. It will surely do the job as a much lower priced and flows more.

As said before the aquamist pump was originally designed for water only. I think in order to design a good water/alcohol injection system, it has to be able to control the flow accurately so one will know the ratio between the gasoline and alcohol or at least predictable. The Aquamist's HSV + the FIA2 or MF2 can easier to adapted for use with alcohol injection/shurflo pump - the HSV seal is made of EPDM and good for most alcohol at high concentration. If you are interested, I can post a schematic on a new thread so it won't alter the thread topic midway.

For your 20% injection rate, it would just be as simple to add 20% of alcohol to your fuel tank to be done with it. If your fear of the leaning up due to the a/f/a ratio, just turn up the fuel pressure a bit to compensate. I remember someone posted this particular method to this board and proved that it is very effective.

The biggest problem facing the usage of alcohol by injecting it as a fuel and not as a coolant - it makes the accurate delivery to each cylinder more difficult especially the log-type manifold/plenum. This critcal factory has to be overcome for a alcohol injection system to be reliable, I suggest the only way to tackle this problem is by using port injection to guarantee even delivery to each cylinder.

Further down the line, the controller that meters the alcohol injection valve has to be mappable and tune exactly as the gasoline injection system. The blockage detection circuitry is also vital since we are offering the system to mostly a DIY market where strict installation procedure is not often followed and debris may be introduced into the alcohol line and blocks one jet. Since alcohol injection is often triggered during boost , one clogged jet can be very bad for the engine.

As I am reasoning my approach to my ideal alcohol injection system, you might as well contact the proper company that supplies the alcohol fuel dragster. It is a subject I know little of and how any alcohol/gasoline engine should be tuned - difficult enough to get tune individually as it is but infinately more complex to tune both with two separate mappable controllers. I think it will be a long time before an aftermarket duel-fuel system is available and the cost? it won't be 399 dollars for sure.

Do you think I am being over-cautious? As hothod has pointed out, WMN has an in-built "fail-safe" mechanism within it. This is the reason I am reading more into the technology as a simple power adder.
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Old 19-03-2005, 03:00 PM
Wet1 Wet1 is offline
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Quote:
Originally Posted by hotrod
Also be advised that some of us have had problems with the shurflo pump at high alcohol concentrations. The pumps commonly sold with the santoprene seals do not like extended service with high concentration alcohol.

Mine lasted about 3 months before the santoprene seals began to leak fluid into the pressure switch.

Shurflo sent me viton components but due to cold weather I have not run the system in several months.

We will find out here in about 8 weeks if the viton is adequat to the task of running >75% alcohol mixes for extended periods.

Larry
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Old 19-03-2005, 03:01 PM
Wet1 Wet1 is offline
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Quote:
Originally Posted by Richard L
Quote:
Originally Posted by hotrod
Also be advised that some of us have had problems with the shurflo pump at high alcohol concentrations. The pumps commonly sold with the santoprene seals do not like extended service with high concentration alcohol.

Mine lasted about 3 months before the santoprene seals began to leak fluid into the pressure switch.

Shurflo sent me viton components but due to cold weather I have not run the system in several months.

We will find out here in about 8 weeks if the viton is adequat to the task of running >75% alcohol mixes for extended periods.

Larry
Thanks for this vital information. I have checked chemical comatibility tables for viton - it came up with inconsistant results- Vital's resistance to methanol is worse than natural rubber (NBR) but according to Dow Corning who holds patent right for viton, there are many types of vitons - one particular one suite methanol. It is just plain confusing. EPDM appeared to be simple and more generic and straight forward and very resist to methanol. I hate trade names especially there are many variations on viton.

I have search many sites for nitromethane compatible seals and came up with three suitable rubber materials PTFE and two others in "trade" name. The cost .... you have to see it to believe it:

PTFE: $1.20 dollars each
Trade name 1: $3.50 each !
Trade name 2: $5.85 each!

The size: 3/16"x 1/16" o-ring - standard imperial size. So we decided to machine our own PTFE seal. Cost is less than $0.1.

Some one is playing silly games.
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