alcohol injection?

Andrei Rinea

Veteran Member
Joined
Jan 21, 2002
Location
Europe, Romania, Bucharest
TDI
VW Tiguan 4Motion 2.0 TDI 170HP (engine CBBB)
.. not in your venes

I saw on VWVortex someone saying something about injecting alcohol in the air pre/post turbo to cool furthermore the air. Is this possible on TDIs? Is it useful/possible in general? A useful application would be cleaning intake but sure sounds funny...
Any input (including "You're an idiot!") is welcome
!
 

Andrei Rinea

Veteran Member
Joined
Jan 21, 2002
Location
Europe, Romania, Bucharest
TDI
VW Tiguan 4Motion 2.0 TDI 170HP (engine CBBB)
here... they say something like this..
My ideea was if I could clean the head intake ports this way since I couldn't clean them when I cleaned (my mechanic and I) the intake manifold. I was hearing something about BioDiesel cleaning slowly the intake but I don't understand how since the BD is injected in the combustion chamber and exits (the combustion gasses) through the exhaust ports not intake...

Methanol could be slowly cleaning crud from there?
 

rwolff

Veteran Member
Joined
Mar 10, 2002
Location
Lesser continental mass, Tosev 3
TDI
None yet
The alcohol in these systems is mainly as an antifreeze for the water - it's the water that does the work. The systems fall into 3 categories:

- Water vapour injection (vacuum line attached to container, suction bubbles air through the liquid), such as the "platinum vapour injector". Extremeley effective at proving Barnum's Law, useless in terms of helping your engine.

- Low-volume water injection. A metered amount of water is injected post-turbo, but it's a small enough volume that it evaporates before it gets into the cylinder. This is basically a chemical intercooler.

- High-volume water injection. A metered amount of water is injected post-turbo, and a fair amount is still liquid when it gets into the cylinder. This is an asymmetric compression ratio booster - it counts on a significant amount of the water still being liquid when the charge fires, with the combustion heat boiling it so "n" (number of molecules of gas - from PV=nRT gas law) on the power stroke is greater than "n" on the compression stroke. This was used on the big radial aircraft engines to boost power on takeoff, and on some WW2 fighter planes to boost "war emergency power" in combat.

Naturally the last one is the most effective (provided your "bottom end" is strong enough), but it has the greatest potential for hydraulic locking if the injection system leaks.
 

clove911

Veteran Member
Joined
Apr 27, 2004
Location
Harford County, Maryland
TDI
2001 Golf, blue
Alcohol can be sprayed into an intake to gain a cleaner burn and add horse power. Propane injection is not as popular with our small motors but alcohol can be burned safely. It really depends how much you use and when.
 

Slave2school

Top Post Dawg
Joined
Mar 20, 2004
Location
Angus, Ontario
TDI
99.5 used to at least...
I have also read that this would improve fuel effiecency...I am sure someone would want to try it for that reason.
 

TooMuchBoost

Veteran Member
Joined
Oct 4, 2004
Location
Blairsville, GA
TDI
Jetta
You need to make some boost with water/meth, but you'll see more of it on these little motors especially considering you can throw away these waste of space inter-coolers with water injection.
 

Slave2school

Top Post Dawg
Joined
Mar 20, 2004
Location
Angus, Ontario
TDI
99.5 used to at least...
No, in the past I have read that this was used in WWII fighter craft to improve flight ceiling (higher boost allowed/methanol injected with the water) and to improve range.
 

Bob_Fout

Oil Wanker
Joined
Sep 5, 2004
Location
Indiana
TDI
2003 Jetta - Alaska Green (sold) / 2015 GTI 2.0T
Water injected jet engines were also used in B-52s.
 

Bob_Fout

Oil Wanker
Joined
Sep 5, 2004
Location
Indiana
TDI
2003 Jetta - Alaska Green (sold) / 2015 GTI 2.0T
No but I'm sure the Air Force is VERY interested in them though


OK....what's a hydrister transmission?
 

whitedog

Veteran Member
Joined
Jul 12, 2004
Location
Bend, Oregon
TDI
2004 Jetta that I fill by myself
Try the search here for "hydristor" and find the thread dedicated to this wonder of wonders.
 
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