First and foremost, huge shoutout to @jyamona for a very much needed table. Thank you!
I had the pleasure of testing cold start for E85 and oem DI only. No PI or JB4 tricks. The results were very impressive. My E85 station stays the same year round even though the temps can reach 20*f in the mornings. Its anywhere between 82-87% according to my ECA and others locally testing it. I find 70*f and 70% to be the threshold of a good start anything less than 70*f and anything more than 70% ethanol will cause long starts and in most cases multiple starts. In the 40-50*f range up to 5-6 start attempts. Although my car is usually garage kept ive been leaving it outside to cold soak for true testing. The ambient temps were 32-34*f (disregard my dash temp, idk why it reads warmer until i start driving) coolant temp was high 30's and fuel temp was about the same. I took some videos of the last 2 days of testing. What i came up with will be a great starting point for most. Obviously your region will vary.
During start AFR's start off around 12.5-12.75:1 and steadily increase to your defined AFR. I use 1 second for cold start duration which mainly controls timing and seems to have little effect on this particular table. This is why there is a small bump in my RPM during start. It does this year round no matter the temperature.
For winter blends and mixtures in the 70-75%
Increase both Red and yellow 40%
For E75-85%
Use the picture as illustrated below.
I added 20% everywhere else as it seems to make starting crisper. Since our fuel scalar doesn’t turn active until the DME enters closed loop I think the extra volume during start definitely helps, you can play with this to see what you think. I’m anxious to see if this solves the heat soak failed start attempt in the dead heat of summer.
I had the pleasure of testing cold start for E85 and oem DI only. No PI or JB4 tricks. The results were very impressive. My E85 station stays the same year round even though the temps can reach 20*f in the mornings. Its anywhere between 82-87% according to my ECA and others locally testing it. I find 70*f and 70% to be the threshold of a good start anything less than 70*f and anything more than 70% ethanol will cause long starts and in most cases multiple starts. In the 40-50*f range up to 5-6 start attempts. Although my car is usually garage kept ive been leaving it outside to cold soak for true testing. The ambient temps were 32-34*f (disregard my dash temp, idk why it reads warmer until i start driving) coolant temp was high 30's and fuel temp was about the same. I took some videos of the last 2 days of testing. What i came up with will be a great starting point for most. Obviously your region will vary.
During start AFR's start off around 12.5-12.75:1 and steadily increase to your defined AFR. I use 1 second for cold start duration which mainly controls timing and seems to have little effect on this particular table. This is why there is a small bump in my RPM during start. It does this year round no matter the temperature.
For winter blends and mixtures in the 70-75%
Increase both Red and yellow 40%
For E75-85%
Use the picture as illustrated below.
I added 20% everywhere else as it seems to make starting crisper. Since our fuel scalar doesn’t turn active until the DME enters closed loop I think the extra volume during start definitely helps, you can play with this to see what you think. I’m anxious to see if this solves the heat soak failed start attempt in the dead heat of summer.