The following is from FAST's help line. While it concerns METHANOL only (not E85), it does indicate the challenges we will encounter tuning our cars to run any fuel other than gasoline!
(Frequently Asked Questions)
"CAN I RUN METHANOL WITH THIS SYSTEM?
- Yes you can. Methanol generally requires a little bit more than twice the volume of fuel over gasoline at full engine load, so you will need much larger injectors to provide an adequate supply of fuel. DO NOT use any fuel system lubricants or fragrance additives in your fuel when running an EFI-equipped vehicle with methanol. Use of these additives will likely result in clogged or damaged injectors.
-A decent way to approximate injector flow requirements for a methanol-burning engine is to simply divide flywheel horsepower by the number of cylinders:
Flywheel HP/# of Cylinders = Injector Flow Rate (lb/hr)
As an example, if you make 800 horsepower with your 8-cylinder engine, you will need a set of 100 lb/hr injectors to provide enough fuel for this engine.
-If you are using methanol on a vehicle being tuned in speed/density mode, you should change the "Injector Flow Rate" setting in the "Fuel Calculation Parameters" section to half of the actual fuel (injector) flow rate. This will cause the ECU to calculate twice the injector pulsewidth it normally would, thereby doubling the volume of fuel to the engine. So, if you were using the set of 100 lb/hr injectors described above, you should enter 50 lb/hr as the injector flow rate. If you are monitoring fuel consumption in lb/hr from C-ComWP, the number shown will be half of what is actually being used by the engine.
If you are tuning in Alpha-N mode, the above information does not apply. You should enter your actual injector flow rate in this case.
- The oxygen sensor will display air/fuel ratios when burning methanol. However, they will be displayed as conventional gasoline air/fuel ratios. This means that the ratio displayed is slightly more than twice as high as the actual ratio; in other words, a displayed air/fuel ratio of 12:1 is, in reality, about 6:1. Also, Lambda values are commonly used when tuning methanol-burning engines. There is a dashboard sensor called "Lambda" in C-ComWP that you can monitor if you are familiar with this measurement standard. Lambda measurements do not vary from one type of fuel to the next."
So, hopefully FAST will update this message for E85. This should be "food-for thought" for ALL OF US contemplating a change to E85!
I will try to modify the above to work for our 6 cylinder engines and post it so everyone can ponder (and correct) it.
Conrad
(Frequently Asked Questions)
"CAN I RUN METHANOL WITH THIS SYSTEM?
- Yes you can. Methanol generally requires a little bit more than twice the volume of fuel over gasoline at full engine load, so you will need much larger injectors to provide an adequate supply of fuel. DO NOT use any fuel system lubricants or fragrance additives in your fuel when running an EFI-equipped vehicle with methanol. Use of these additives will likely result in clogged or damaged injectors.
-A decent way to approximate injector flow requirements for a methanol-burning engine is to simply divide flywheel horsepower by the number of cylinders:
Flywheel HP/# of Cylinders = Injector Flow Rate (lb/hr)
As an example, if you make 800 horsepower with your 8-cylinder engine, you will need a set of 100 lb/hr injectors to provide enough fuel for this engine.
-If you are using methanol on a vehicle being tuned in speed/density mode, you should change the "Injector Flow Rate" setting in the "Fuel Calculation Parameters" section to half of the actual fuel (injector) flow rate. This will cause the ECU to calculate twice the injector pulsewidth it normally would, thereby doubling the volume of fuel to the engine. So, if you were using the set of 100 lb/hr injectors described above, you should enter 50 lb/hr as the injector flow rate. If you are monitoring fuel consumption in lb/hr from C-ComWP, the number shown will be half of what is actually being used by the engine.
If you are tuning in Alpha-N mode, the above information does not apply. You should enter your actual injector flow rate in this case.
- The oxygen sensor will display air/fuel ratios when burning methanol. However, they will be displayed as conventional gasoline air/fuel ratios. This means that the ratio displayed is slightly more than twice as high as the actual ratio; in other words, a displayed air/fuel ratio of 12:1 is, in reality, about 6:1. Also, Lambda values are commonly used when tuning methanol-burning engines. There is a dashboard sensor called "Lambda" in C-ComWP that you can monitor if you are familiar with this measurement standard. Lambda measurements do not vary from one type of fuel to the next."
So, hopefully FAST will update this message for E85. This should be "food-for thought" for ALL OF US contemplating a change to E85!
I will try to modify the above to work for our 6 cylinder engines and post it so everyone can ponder (and correct) it.
Conrad