knock counts and water injection
10-31-2007, 05:06 PM
#61
Rennlist Member
pjburges;
get a piece of aluminum and put on a few drops of methanol
Let it sit for a few seconds, and then blow on it to get it to evaporate quicker; so total of quite a few seconds of contact time.
You will notice no corrosion (oxidation; same thing) or left over residue, and this is with full liquid methanol contact (not even vapor).
They say, just don't leave it in your engine or fuel system, or on your paint, for many hours or days; that's all.
A. Wayne;
I definitely agree that it should not be used as a bandaide solution, and it's true, alot of people do.
One should start with an efficient turbo, IC, and proper tuning. But, eventually cylinder pressures get too high for the available pump octane. Although water doesn't contribute to the octane rating of the fuel, I would say it definitely contributes to the anti-knock properties of the system. It smooths out and moderates the flame propagation. It reduces peak cylinder pressure while maintaining BMEP. Too much straight water lowers peak cylinder pressure so much that the average cylinder pressure (BMEP) goes down. I will say that the injection amount window to achieve this might be a little on the small side. A mix with methanol will be more forgiving.
Geneqco;
"you would suggest using a mix but to use that mix sparingly so as to avoid a potential hp loss. You'd also be comfortable that provided and excessive amount wasn't used there'd be no issue of lubricant washing or residual deposits and therefore no downside?"
Absolutely
Now, the question is: how much is this "sparingly amount"
Have to revert back to science books and find out how much heat water can take out of a system.
That aquamist site is a good one, but it doesn't mention anything about dewpoint.
get a piece of aluminum and put on a few drops of methanol
Let it sit for a few seconds, and then blow on it to get it to evaporate quicker; so total of quite a few seconds of contact time.
You will notice no corrosion (oxidation; same thing) or left over residue, and this is with full liquid methanol contact (not even vapor).
They say, just don't leave it in your engine or fuel system, or on your paint, for many hours or days; that's all.
A. Wayne;
I definitely agree that it should not be used as a bandaide solution, and it's true, alot of people do.
One should start with an efficient turbo, IC, and proper tuning. But, eventually cylinder pressures get too high for the available pump octane. Although water doesn't contribute to the octane rating of the fuel, I would say it definitely contributes to the anti-knock properties of the system. It smooths out and moderates the flame propagation. It reduces peak cylinder pressure while maintaining BMEP. Too much straight water lowers peak cylinder pressure so much that the average cylinder pressure (BMEP) goes down. I will say that the injection amount window to achieve this might be a little on the small side. A mix with methanol will be more forgiving.
Geneqco;
"you would suggest using a mix but to use that mix sparingly so as to avoid a potential hp loss. You'd also be comfortable that provided and excessive amount wasn't used there'd be no issue of lubricant washing or residual deposits and therefore no downside?"
Absolutely
Now, the question is: how much is this "sparingly amount"
Have to revert back to science books and find out how much heat water can take out of a system.
That aquamist site is a good one, but it doesn't mention anything about dewpoint.
10-31-2007, 05:25 PM
#62
Alusil as we know is just a hypereuretic alloy, an aluminum high in silicon content (over 14% I think makes it hyper). I don't know how that would factor in with methanol, which is much more corrosive than ethanol.
The big issue with the top end is the non-lubricity of alcohol.
