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Yeah I get it, I almost didn't write the last couple posts after really looking at the scales that Temp posted. It seems that lambda doesn't exactly work as advertised. The theory sounds great but when you start looking at application it kinda falls apart when you try to apply it to multiple fuels simultaneously. Maybe Haltech will have the answer with their fuel blending strategy.
Jesus, don't stop posting. This is great info that stimulates the mind (or my mind anyway). The info you've provided and provoked in this thread are why I come to this forum lol.

Isn't it true that a wideband O2 sensor only reads lambda and the fuel selection converts the lambda value into the equivalent fuel ratio for display based on fuel selected? i.e. when configured using gas scale and a target configured for 11.3 for WOT, whatever fuel you dump in the tank is going to generate a lambda value and with fuel correction should readout close to 11.3?
This^^^is how I've viewed AFR readings since I began to understand what AFR is.



The discussion here has convinced me that I've been killing myself with E85 and adding meth to control intake temps. This thread has me looking at logs from the past year to determine where to come up an idea of what I need to do. Over a year ago I swapped to C16 because I didn't have enough injector to run E85. I added 50/50 water/meth because my injectors were at 90% DC on C16. The added fuel in the meth/water mix helped me go faster (I think). When I swapped the fuel system to E85 I continued with the water/meth injection and now I believe that I might be hurting because of the mix of fuels. It appears, from the comments here, that I have been putting too much concern in IAT's when on E85.

I wish this thread would've occurred two months ago so I could do some testing without the meth/water injection because now I have to wait months to find out - smh (I need to move south lol.)

I've never been much of a plug reader at the track. On a dyno, sure, but at the track I've never pulled one. I guess that describes the level I'm at.
 

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Well, let me be the one dummy that thinks you weren't exactly on the wrong planet with your method....with one exception. The water. When you mixed the methanol and the water, it was no longer a fuel, because frankly it isn't flammable anymore. It takes very little water to ruin the flammability of methanol. But straight methanol? No problem with that. The one risk you have is if you hickup the motor, the methanol mist in the air piping could ignite.

As far as mixing fuels: I don't give a shit and I don't think your engine does either. As for the target a/f readings.....well even with one fuel, those can be significantly different in different combos. So don't get caught up in it. Read the plugs. Read them at the track. When you get a plug that you like the looks of, take note of the a/f reading and boost level. Now you have one target datapoint.

Believe me, your fuel system is main stream compared to mine. Yes it can create tuning challenges. Tuning is challenging. Just remember that your methanol is a buffer to your tune. If you get 20% from the methanol, you will have to account for that and change your e85 charts more because of it to get the effect you are after. I'd do it. But then, my setup is not conventional in some regards.
 

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A couple of observations. The water in the water/meth mix isn't going to affect the combustion, by the time the spark plug ignites you basically have everything vaporized and the flame will still find the meth though the water does slow it down and lower the combustion's maximum temp.

As far as reading spark plugs, in my opinion it's not as important as a lot of guys state. I've probably only "read" a spark plug once or twice in 13 years of running my combo which during which I've had 1300 passes. This includes using gas, ethanol and methanol. Never hurt anything except early on in 2009 I had a snafu in the ECU software bite me and I burned a head gasket.
 

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^^^^X2^^^^ The water doesn't mix with the alcohol persey, it actually fits between the molecules and takes up the empty space. Do this cheap little experiment if you doubt my statement. Take 1 cup of rubbing alcohol and 1 cup of water in a 2 cup or larger measuring cup or graduated cylinder. Pour one into the other and see what the volume measures. I guarantee you there is not 2 cups of liquid when combined. Nothing is chemically altered when they are combined they simply fit together very efficiently.
 
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That adds up to me. But that's basing my findings on AFR readings.

I was between 91-94%DC on a set of deka 80lb'ers on C16 at 21-22psi of boost. I added the 50/50 meth injection and that dropped the DC to 80-82%. Both at the same AFR give or a take .1-.2 AFR. This occurred as soon as I added the meth and the tunes were very similar along with trap speed. At the time I couldn't get the car off the line which is hard to believe that it was worse than it is now lol.
 

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Do you have enough pump capacity to just go up on base pressure?? I have run 75psi base for years and honestly I am not afraid to go even higher if the need arises. That should take care of your capacity issues if you have a pump that will move enough fuel. There are a number of calculators available to work out the new capacity.
 

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^^^^X2^^^^ The water doesn't mix with the alcohol persey, it actually fits between the molecules and takes up the empty space. Do this cheap little experiment if you doubt my statement. Take 1 cup of rubbing alcohol and 1 cup of water in a 2 cup or larger measuring cup or graduated cylinder. Pour one into the other and see what the volume measures. I guarantee you there is not 2 cups of liquid when combined. Nothing is chemically altered when they are combined they simply fit together very efficiently.
This clears something up that has bothered me for years. When I test the E content in my fuel. Per instruction I use 50 ml of fuel and 48 ml of water in a 100 ml graduated cylinder. And do not end up with 98 ml.
Thanks (y)
 
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