waterinjection.info  

Go Back   waterinjection.info > Injection Theory (what it is and what it does) > Injection Mixtures

Reply
 
Thread Tools Display Modes
  #1  
Old 17-03-2005, 06:22 PM
stu stu is offline
Junior Member
 
Join Date: Sep 2004
Location: NM
Posts: 3
Default water + denatured alcohol

Hey everybody I just had one quick question I am currently running a sureflow pump and was wondering what a good mix of water to denatured alcohol would be recomended. I have searched but only found bits and pieces of this info.

Thanks Jeff
Reply With Quote
  #2  
Old 17-03-2005, 07:26 PM
hotrod hotrod is offline
Senior Member
 
Join Date: Oct 2003
Posts: 307
Default water alcohol mix

You will find most folks start with a 50/50 mix of water and alcohol if they are running methanol (wood alcohol) or denatured alcohol (ethanol).

Its a good reliable mixture that has lots of published data to back it up. Its been the default recommedation for about 60 years, and is still commonly used in unlimited airplane racing and unlimited hydroplane racing where there are no rules that force them to run straight water like in WRC.

After you get some experience with it some folks investigate higher alcohol mixes but many find all the preformance they need with the 50/50 and for those who live in areas that can freeze in the winter time it gives adequate freeze protection as well.

Larry
Reply With Quote
  #3  
Old 17-03-2005, 07:37 PM
stu stu is offline
Junior Member
 
Join Date: Sep 2004
Location: NM
Posts: 3
Default

Thanks I was hoping I would get a reply from you, you seem to know what whats up with the subie and water injection. what would be the best a/f/w ratio? I am tuning with the hydra, I was planing on 12:0 afr at red line on 19 psi with an 18 g

Thanks Jeff
Reply With Quote
  #4  
Old 20-03-2005, 02:57 AM
hotrod hotrod is offline
Senior Member
 
Join Date: Oct 2003
Posts: 307
Default guessing

Quote:
what would be the best a/f/w ratio?
Sort of difficult to give a hard and fast number, so will throw out these guide lines. The really serious racers ie folks like the unlimited air plane racers running boost pressures near 30- 50 psi and all the WWII combat aircraft generally used 50/50 mixes of water methanol at a .5 lb ADI fluid to 1 lb fuel rate. That is pretty much an upper limiting case situation so you can safely assume you won't have to go above (or probably near that ).

Most recommendations are to start in the 10% to 25 % fuel to injection fluid range.

Lets say your running a 40 lb/min turbo (about 400 hp) at a 12.0:1 AFR that means your flowing about 3.3 lb/min fuel. Your 10% low limit would be 0.33 lb/min of WI fluid and your 25% upper limit would be 0.83 lb/min.

Depending on how you spec you nozzles you are probably interested in either cc/min or gal / hr flow rates.

0.33 lb/min = 150 cc/min or about 2.4 gal / hr
0.83 lb/min = 380 cc/min or about 5.9 gal/hr

My total flow in all my nozzles for the stock turbo has generally been 3 or 4 gal per hour and was probably a bit high. ( I did not have the tools to tune it, on the edge, so went on the safe side)

I've seen a few higher but I don't recall anyone using less than 2 gal/hr rates.

My best guess not knowing your setup, would be to start with about 4 gal/hr ( 250 cc/min) rates and work from there either up or down as your tuning indications suggest.

I generally figure rates based on air flow rather than fuel flow, and like numbers in the 2% (by weight) of max power air flow as a typical safe starting point.

Thinking in those terms the .5 lb ADI to 1 lb fuel used by the unlimited guys figures out to be 4% of air flow on a 12.5:1 fuel air ratio.
25% fuel/WI rate comes out to 2% of airflow on a 12.5:1 fuel air ratio.
10% fuel/WI rate comes out to .8 % of air flow on a 12.5:1 fuel air ratio.

If you figure based on air flow you don't have to refigure each time you lean out the mixture. Air flow is also handy because you can guesstimate your air flow based on hp or guess your hp based on air flow. It takes about .105 lb of air to make 1 hp, so to make 400 hp (at the crankshaft) you need about 42 lbs/min air flow.

So for a quick and dirty calculation take your estimated crankshaft hp and mulitply by either of the following factors to get a starting point injection rate of 50/50 WI .

for gal/hr rates ----- hp x 0.0144 = WI gal/hr
for cc/min rates ----- hp x 0.9080 = WI cc/min

Hope that helps?

Larry
Reply With Quote
  #5  
Old 20-03-2005, 04:45 AM
stu stu is offline
Junior Member
 
Join Date: Sep 2004
Location: NM
Posts: 3
Default

Thanks Larry your the man
Reply With Quote
  #6  
Old 13-06-2005, 03:32 PM
CorradoG60 CorradoG60 is offline
Junior Member
 
Join Date: Jun 2005
Posts: 1
Default

What is the disadvantage of ethylalcohol ?
I read somewhere that methanol should be prefered.
Reply With Quote
  #7  
Old 03-02-2009, 07:36 PM
mizzupowa mizzupowa is offline
Junior Member
 
Join Date: Feb 2009
Location: Rome, Italy
Posts: 2
Default

Hello, i'm using a mixture composed like that :

2 liters of distilled water

1 liter of denaturated alcohol







do you think that, because the alcohol is not PURE (the WHITE one)
i will have any of those problems ? :

1) malfunction / ostruction of the injectors

2) engine problems due to the color of the alcohol

thanks !!!
__________________
in doubt....keep it down !
Reply With Quote
  #8  
Old 04-02-2009, 09:55 AM
raddy raddy is offline
Member
 
Join Date: May 2006
Posts: 40
Default

1, no problem
2, no problem
Reply With Quote
  #9  
Old 04-02-2009, 10:05 AM
mizzupowa mizzupowa is offline
Junior Member
 
Join Date: Feb 2009
Location: Rome, Italy
Posts: 2
Default

ok thanks, pal !

but really really sure that the COLORANT in the alcohol will not "close", slowly and daily, the injectors?
or, worse, if it goes in the engine piston chamber, it will not burn and stay over there day after day accumulating ?

it's only that i've just found this Aquamist in the EVO IX when i bought it in June 2008, but the person that made all the stuff
is in another city of Italy (700km from Rome) and doesn't wants to give me at least phone advices about maintenance or other
things ! :cry:
__________________
in doubt....keep it down !
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +1. The time now is 09:15 PM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.