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cs Guest
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Posted: Wed Aug 08, 2001 7:47 pm Post subject: |
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does anyone have any experience with alcohol injection. if so please explain how difficult/expenxive the process is and the possible gains. |
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Dave Guest
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Posted: Thu Aug 09, 2001 1:11 am Post subject: |
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The only thing I know about it is that you will have to rebuild your engine Alot because it eats alumanum. But your engine will run alot cleaner and cooler.
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Rick MacLaren Guest
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Posted: Thu Aug 09, 2001 3:31 am Post subject: |
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I have not heard of alcohol eating aluminum - I'd like to see verification of that claim - so if you hear more let me know cause I don't wanna blow up my engine. I did ask my boss who has a Ph.D. in chemistry and he doesn't know of any violent reactions happening with alcohol on aluminum. He says that aluminum has a layer of oxidant that naturally occurs from it's contact with oxygen in air. This same layer of oxidant actually serves as a protectant against further oxidization.
Perhaps this rumour started because some guys injected the alcohol BEFORE the turbocharger...the result was that the impeller blades were eaten away from hitting the alcohol - but this would happen even if the impeller blades were hitting water or grape jelly. So, of course, this degradation has more to do with the laws of mechanics than those of chemistry. I guess I'll wait to hear back from Dave as to what that's all about.
I have heard, through guys racing Grand Nationals and using alcohol/water mix, that the alcohol portion of the cocktail WILL eat away at rubber and plastics.
http://www.geocities.com/rad87gn/tech/alcohol.html
My solution to the 'alcohol eating rubber and plastics' problem is to dilute the mix. Simple. I've seen Grand National guys running for two years now with no rebuilds in sight.
Methanol:
100%: 1.08 lb/min of methanol will vaporize, cooling the air from 150 F to 96 F.
50%: 0.55 lb/min of methanol/water will vaporize, cooling the air from 150 F to 107 F
Ethanol:
100%: 1.26 lb/min of ethanol will vaporize, cooling the air from 150 F to 100 F.
50%: 0.57 lb/min of ethanol/water will vaporize, cooling the air from 150 F to 108 F
Isopropyl:
70%: 0.76 lb/min of alcohol will vaporize, cooling the air from 150 F to 107 F.
91%: 1.14 lb/min of alcohol will vaporize, cooling the air from 150 F to 104 F.
100: 1.50 lb/min of alcohol will vaporize, cooling the air from 150 F to 102 F.
And if you're completely scared away from alcohol by the rumour that alcohol eats aluminum, just use 100% water...you still will get a 30 to 40 degree drop in head temperature...it's been used to cool engines since WWII, and remember, alcohol was used in car radiators up until the invention of glycol. It has a long history.
The benefits to alcohol are straightforward.
1. Reduce head temperature...increase head life.
2. Reduce detonation thus allowing increase in boost.
3. Cleans the intake and valves - indeed, it appears in three products I've investigated to clean your fuel injection.
4. Tastes good when you swig it and you can rub it on your shaving cuts.
Good luck.
_________________
1980 Porsche 931 C6H12O6 injected 15 PSI
1979 Porsche 924
[ This Message was edited by: Rick MacLaren on 2001-08-09 07:13 ] |
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larso Guest
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Posted: Thu Aug 09, 2001 9:00 am Post subject: |
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what exactly is the point of alchol in the mixture, water has a very high specific heat capacity, i could only see using alcohol if you were driving in the winter and were worried about freezing...
Rick, have you got soem info for me???
Same with coolant in your engine, 100 percent water is better than a coolant mix. |
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Dave Guest
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Posted: Thu Aug 09, 2001 3:03 pm Post subject: |
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I am not sure where I heard that rumor I think it was from some stupid Iroc kid at work. WHy do alot of race cars that have NOS run special valves???
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cs Guest
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Posted: Thu Aug 09, 2001 4:38 pm Post subject: |
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hey rick, what type of setup do you have and how much did it cost. thanks |
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Rick MacLaren Guest
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Posted: Fri Aug 10, 2001 9:47 am Post subject: |
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Alcohol has been used as an engine coolant for longer than glycol. Even glycol is an alcohol-based product.
The history behind it is that during WWII the US needed to cool engines and prevent premature detonation (we don't want to be premature now do we?) and scientists injected small amounts of alcohol, alcohol and water mix, and water into the cylinder heads of planes and land vehicles. The result was dramatic...
http://naca.larc.nasa.gov/reports/1945/naca-wr-e-264/naca-wr-e-264.pdf
...in this controlled study, you can see on pages 3 and 4 how much the reduction in temperature was given small amounts of alcohol and water injected into the airstream as a fine mist. Notice in the second-last figure how the knock limited pressure thresholds are so much higher for the alcohol and water mix. It's impressive.
My system is currently undergoing some revision, and it's turned off right now until I install a couple of gauges (exhaust temperature and knock sensor) and revamp it, but I'll give the main ingredients. (I haven't really introduced it to my coworkers yet, who are, I think, dying to see it) It's important, I've learned, to decide HOW you'll switch on the pump well in advance of buying your materials. My preference is to have the pump activated by PSI - but this wasn't always the case, I've learned that a throttle-activated mechanism uses WAAAY too much alcohol.
1. You need a NOS-type nozzle to present a small mist into the intake, cost $40 CDN at Performance Products. I got a similar nozzle at a furnace supply house. Same thing really.
2. You need hoses to carry water/alcohol from the water container, like your windshield washer container, to the nozzle, cost $20 CDN at Princess Auto - I bought the ones for air brushes.
3. You need a small pump to handle the flow of alcohol and water, cost $140 CDN Holly fuel pump. You can use an old windshield washer pump from Lars' car if you wish.
4. Gadgets like a pressure switch to activate at 5 PSI, bleeder valves, nipples (my personal favourite), cost $40 CDN.
The basic premise is that once pressure after the turbo exceeds 5 PSI, the system switches the pump on and a mist of diluted alcohol and water is injected into the system...the nozzle looks like a needle, or, on some cars, I've seen a mister comparable to the ones you see in the meat counter at your local deli...sprays water on the meat. Once your meat is injected with alcohol and water, it cools down, detonation happens just as if you were running 110 octane - no predetonation.
The first time I saw this done in a systematic way was at St. Thomas dragway near London Ontario and there they ran the same system on a Buick Grand National. He pulled 21 pounds of boost.
I've got a guy making up a kit for me. I'll give his email once it is done and he gives permission. I'm sure he'll be happy to help you along if you choose to do it. I'm paying less than $100 US without the pump.
The guys here do it commercially...
http://www.aquamist.co.uk/
_________________
1980 Porsche 931 C6H12O6 injected 15 PSI
1979 Porsche 924
[ This Message was edited by: Rick MacLaren on 2001-08-10 09:55 ] |
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cs Guest
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Posted: Sat Aug 11, 2001 3:17 pm Post subject: |
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let me know when your guy is through with your kit, that is if he's willing to help me out. |
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larso Guest
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Posted: Sun Aug 12, 2001 3:34 am Post subject: |
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Rick i've heard all that before but u never answered my question about why use alcohol? WHy not use 100 percent water, 100 percent water cools much better than a coolant mix...and it sucks heat out of your combustion process more than alcohol does (higher sp. ht. capacity).
I believe planes fly at high altitudes and in Russia and scandinavian countries and germany, it was cold so the water would freeze etc., so that is why they used alcohol...what is the point of using alcohol in our driving conditions is what i meant to get at???Is alcohol useful in any way other than stopping freezing?
water has about twice the SHC of alcohol, is the problem that water is too slow to absorb the heat in the process?
is alcohol a better conductor of heat??
[ This Message was edited by: larso on 2001-08-12 03:46 ] |
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924RACR
Joined: 29 Jul 2001 Posts: 8803 Location: Royal Oak, MI, USA
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Posted: Sun Aug 12, 2001 4:03 am Post subject: |
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Alright, any more talk of beef injections and I'm gonna wipe this whole thread off...
Sounds very cool, Rick, well laid out... pardon the pun!
Y'know, one of these days we should have a 924.org meet (NOT MEAT!) somewhere in Ontario, I think... seems like it's pretty central to so many of us... I mean, I'm only about 1.5hrs away from London over here in Detroit, and the guys from NY and PA and OH could also make it... maybe I should post to some more central locations, see if there's interest... Rick, please email me if you can, we can try to come up with some ideas for a specific location...
_________________ Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype |
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larso Guest
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Posted: Sun Aug 12, 2001 5:46 am Post subject: |
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Ya well Alberta is no where near ontario, i am closest to washington, oregon, idaho, montana, right above them.
ONtario is basically in the USA, toronto is hanging down there as if it wants to be part of USA, the people there act like americans (accept where dwak lives), toronto is basically the detroit of canada! u have it easy you guys, don't know why you haven't bumped into each other yet :wink:
[ This Message was edited by: larso on 2001-08-12 05:46 ] |
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Rick MacLaren Guest
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Posted: Sun Aug 12, 2001 9:47 pm Post subject: |
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Hi,
Lars you asked me why use alcohol instead of water. I just want to remind you that I'm not a chemist and I dropped out of Chemistry 101 in favour of Anthropology (better chick/geek ratio in Anthropology than Chemistry). So I know squat about chemistry. So let's look at just the empirical evidence - and I'll try to write this in a matter of fact scientific way, but forgive me if it looks snooty.
First, from the cases out there where the Grand National guys have experimented with these mixtures, they have found that a mix results in excellent cooling, but I've never seen them compare this mix to pure alcohol or pure water. Second, in that US Military report I posted above, I was just reading the following:
"The water-alcohol mixture used was a solution of 25% ethyl alcohol, 25% methyl alcohol, and 50% water by volume, which has been considered by the Air Technical Service Command, Army Air Forces, as a suitable internal coolant"
It gets cold up there in the clouds, so I suspect, Lars, that you're right about the alcohol also serving the purpose of preventing freezing. You've raised good questions about the alcohol and it's physical properties compared to water, but I just don't have the physics and chemistry background to answer your questions about alcohol properly. Aside from saying that the cocktail mixture works I don't know what to say. I'm using the cocktail 50:50 mix unless someone comes up with something better. I'll even use distilled water alone if that cools best.
Water - I suspect it is primarily cooling.
Alcohol - It might be higher octane?
Either way, the thing works with water alone - I was running with a boost controller and 15 PSI with and without alcohol.
I got my new kit Friday. I wrote to the guy who made up my second kit, and he replied...
"If you want to post to your club board, I'd welcome it. Thank you very much for the publicity." Darren Dawes
Darren's website is...
http://www.dawesdevices.com/water.html
In Darren's kit, I got a 40 PSI pump, which means I can use the Holly fuel pump I bought for other nefarious purposes. His kit also has nice controls built in to ensure that alcohol or water doesn't seep into your intake when you don't want it there. The nozzle he sent me is good, but my existing NOS nozzle is best (expensive too...$40 CDN)- it is used to inject nitrous at a 90 degree angle inside the aluminum intake arm. I tried fitting Darren's nozzle into my intake and it's a tad too big for my liking. It'll work, yes, but I want zero restriction and I already bought the NOS nozzle anyways so I'm keeping it. His 5 PSI switch and the other items work perfectly on a trial setup.
Vaughan, I'll write to you presently about a meet...
Rick
_________________
1980 Porsche 931 C6H12O6 injected 15 PSI
1979 Porsche 924
[ This Message was edited by: Rick MacLaren on 2001-08-12 22:13 ] |
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