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Active Member
- Joined
- Apr 22, 2021
- Messages
- 208
- Reaction score
- 84
- Points
- 28
- Location
- Memphis, TN
- Vehicle Year
- 1987
- Make / Model
- Ford Ranger
- Transmission
- Automatic
So my Ranger project (other threads) is a 5.0l, blown (blow thru), ATM Innovations E85 carb tuned by Angela Neely at ATM for the application.
(All theoretical as the engine has not been stabbed in the car yet but parts are here in total).
Other threads also highlight my alcohol fuel plant that will produce E98 (really more like E95 with some water) for the same engine. I had discussed with Neely a second mod to the carb for E95 after a period of testing/debug on pump E85. I didn’t ask a dumb question, is the mod needed?
So in doing some research I came by an Alcohol Content Analyzer that is real time and has can bus out, display, etc. it uses a GM flex sensor of course. I also learned that it specifically measures percentage of gasoline with a contaminant (alcohol, water, etc) that is not petroleum based. Therefore an output of E15 means 85 percent gas detected in a solution of X, not 15 percent measured alcohol!
With a carb of course there is no fuel control once jetted and set, unlike EFI. Using a microsquirt for ignition, boost control and data logging only, there is no direct fuel control of any kind that is dynamic.
Being a cheap ass, I really don’t want to buy a $800 carb and then send it off again for another mod in 6 months.
I’d also like to be able to have some liberty to run pump E85 or E95 interchangeably (I know EFI fixes that!!) and have a dynamic control over “protection mechanisms” when fuel quality is E55 and not E85 or worse yet I am running my E95 and have to blend with Texaco pump corn juice with lots of gas in it for winter blend. The carb will behave as it will, I will have no idea unless I spend time testing content of multiple fuels and then test a blended sample from the tank, what the fuel quality is.
Ridiculous!!
I got to thinking:
Squirt can accept AFR wide band input (which is a logged function I had planned for carb tuning), it can display that as well. It also can accept the output from the flex sensor via the can bus from the Alcohol Analyzer device.
If the flex sensor is placed immediately between fuel pressure regulator (firewall mounted bypass style) and the carb bowl, that is as close to real time as can be. As fuel quality changes (I.e, gasoline content, which is the evil I detest, raising detonation propensity), the ignition and boost controls can be mapped to retard and reduce, respectively.
So I drive 1000 miles. I get 20 gallons of my E95 in the tank, I get 350 miles. Uhoh, I need fuel. The only convenient option is a pump E85 fill. So I have jetted and tuned all for E95 at my altitude, it’s optimal and richer to the end of safety. I add E 85 which is probablyreally crappy E60. Now I have a goofy blend that is seriously different from my E95. Tuning is shot…..
But maybe not-
E85 stoic is 9.8:1
E100 stoic is 9.0:1
Thas is only <1.0 difference, unlike 14.7:1 vs 9.8:1 (dramatic).
The question:
Might a carburetor optimized for E85 (and probably designed and calculated based on certified E85 ASTM fuel., ) remain in a viable jetting window (albeit it might be a bit richer everywhere) that would allow deflection to E51 (ASTM min) and up to E95 (my fuel)???
Rich is good, lean is bad. It would be heading in the rich direction adding GAS percentage to the fuel in all cases.
The idea of having a simple detonation protection mechanism (alcohol content derived) real time, allowing Squirt to back timing off and back off boost would be pretty beneficial.
So maybe have carb set for E95, which will produce a rich condition as fuel quality deteriorates at times to E51. I never go lean, have ideal power at E85/95 window. As fuel degrades, timing is pulled and boost pulled.
I don’t think it is a plug fouling rich it would hit.
But then again, most every car on the road with flex fuel sensor has EFI and fueling is precise with any fuel quality.
And an E85 carb is probably best suited for use with VP E85 (certified fuel).
Hoping someone with some tuning experience can chime in on the potential AFR shift.
I guess it comes down to basic math.
Example:
If idle is best at 13:1, shifting the fuel by 0.8 (stoic diff) puts it at 13.8:1 or 12.2:1
Is a shift in AFR of 0.8 at idle, cruise or WOT really really noticeable? Like catastrophic noticeable????
I suppose if it’s at the edge and falls off the cliff, yes it’s bad, but it would have already been Uber rich or lean to fall off said cliff——- with a 0.8 shift.
But if I’m the middle of a range—- and it goes a bit richer by 0.8—- would it be terrible?
Protection from detonation and flexibility to not be tied to my fuel plant—— and still have a modest driveability…… not harming engine, washing cylinder walls, oil dilution, etc.) is what I am after.
Im not going EFI!!
appreciate any insight that might be sent my way.
(All theoretical as the engine has not been stabbed in the car yet but parts are here in total).
Other threads also highlight my alcohol fuel plant that will produce E98 (really more like E95 with some water) for the same engine. I had discussed with Neely a second mod to the carb for E95 after a period of testing/debug on pump E85. I didn’t ask a dumb question, is the mod needed?
So in doing some research I came by an Alcohol Content Analyzer that is real time and has can bus out, display, etc. it uses a GM flex sensor of course. I also learned that it specifically measures percentage of gasoline with a contaminant (alcohol, water, etc) that is not petroleum based. Therefore an output of E15 means 85 percent gas detected in a solution of X, not 15 percent measured alcohol!
With a carb of course there is no fuel control once jetted and set, unlike EFI. Using a microsquirt for ignition, boost control and data logging only, there is no direct fuel control of any kind that is dynamic.
Being a cheap ass, I really don’t want to buy a $800 carb and then send it off again for another mod in 6 months.
I’d also like to be able to have some liberty to run pump E85 or E95 interchangeably (I know EFI fixes that!!) and have a dynamic control over “protection mechanisms” when fuel quality is E55 and not E85 or worse yet I am running my E95 and have to blend with Texaco pump corn juice with lots of gas in it for winter blend. The carb will behave as it will, I will have no idea unless I spend time testing content of multiple fuels and then test a blended sample from the tank, what the fuel quality is.
Ridiculous!!
I got to thinking:
Squirt can accept AFR wide band input (which is a logged function I had planned for carb tuning), it can display that as well. It also can accept the output from the flex sensor via the can bus from the Alcohol Analyzer device.
If the flex sensor is placed immediately between fuel pressure regulator (firewall mounted bypass style) and the carb bowl, that is as close to real time as can be. As fuel quality changes (I.e, gasoline content, which is the evil I detest, raising detonation propensity), the ignition and boost controls can be mapped to retard and reduce, respectively.
So I drive 1000 miles. I get 20 gallons of my E95 in the tank, I get 350 miles. Uhoh, I need fuel. The only convenient option is a pump E85 fill. So I have jetted and tuned all for E95 at my altitude, it’s optimal and richer to the end of safety. I add E 85 which is probablyreally crappy E60. Now I have a goofy blend that is seriously different from my E95. Tuning is shot…..
But maybe not-
E85 stoic is 9.8:1
E100 stoic is 9.0:1
Thas is only <1.0 difference, unlike 14.7:1 vs 9.8:1 (dramatic).
The question:
Might a carburetor optimized for E85 (and probably designed and calculated based on certified E85 ASTM fuel., ) remain in a viable jetting window (albeit it might be a bit richer everywhere) that would allow deflection to E51 (ASTM min) and up to E95 (my fuel)???
Rich is good, lean is bad. It would be heading in the rich direction adding GAS percentage to the fuel in all cases.
The idea of having a simple detonation protection mechanism (alcohol content derived) real time, allowing Squirt to back timing off and back off boost would be pretty beneficial.
So maybe have carb set for E95, which will produce a rich condition as fuel quality deteriorates at times to E51. I never go lean, have ideal power at E85/95 window. As fuel degrades, timing is pulled and boost pulled.
I don’t think it is a plug fouling rich it would hit.
But then again, most every car on the road with flex fuel sensor has EFI and fueling is precise with any fuel quality.
And an E85 carb is probably best suited for use with VP E85 (certified fuel).
Hoping someone with some tuning experience can chime in on the potential AFR shift.
I guess it comes down to basic math.
Example:
If idle is best at 13:1, shifting the fuel by 0.8 (stoic diff) puts it at 13.8:1 or 12.2:1
Is a shift in AFR of 0.8 at idle, cruise or WOT really really noticeable? Like catastrophic noticeable????
I suppose if it’s at the edge and falls off the cliff, yes it’s bad, but it would have already been Uber rich or lean to fall off said cliff——- with a 0.8 shift.
But if I’m the middle of a range—- and it goes a bit richer by 0.8—- would it be terrible?
Protection from detonation and flexibility to not be tied to my fuel plant—— and still have a modest driveability…… not harming engine, washing cylinder walls, oil dilution, etc.) is what I am after.
Im not going EFI!!
appreciate any insight that might be sent my way.
