E85 Questions

Are you saying he just filled his empty tank with e85? If so, what other mods did he do to it? I’m just starting to read about e85 in cars not flex fuel certified, so please go easy on me. Thanks!
Yeah, some cars on Facebook are reporting running full E85 (no mix) with Lap3 2.5 tune. Some run out of pump volume (pressure drops) at E40, some at E60, some can run full E85.

Various other mods (CPI, HPFP, methanol) are meant so all cars can run straight E85, if desired.

Jb4 needs cpi or hpfp + BEF (back end flash), and they're still working out some of the kinks, as far as I can tell. Some people are running E85 with jb4 + BEF, and maybe nothing else.

Other tuners like sxth are also working to enable full E85, I believe. And I saw Lozic also post something about it recently.
 
Yeah, some cars on Facebook are reporting running full E85 (no mix) with Lap3 2.5 tune. Some run out of pump volume (pressure drops) at E40, some at E60, some can run full E85.

Various other mods (CPI, HPFP, methanol) are meant so all cars can run straight E85, if desired.

Jb4 needs cpi or hpfp + BEF (back end flash), and they're still working out some of the kinks, as far as I can tell. Some people are running E85 with jb4 + BEF, and maybe nothing else.

Other tuners like sxth are also working to enable full E85, I believe. And I saw Lozic also post something about it recently.
Thanks for the input. I wonder if one could run 87 gas and play with e85 mix to brig octane rating up to 95 for map 3. It would be an interesting experiment. Does BMS offer a backin flash? I haven’t heard that.
 
This site gave me the idea. Shows hoe to get e85 mixed with 87 octane to get 97 octane rating.
 
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Are you saying he just filled his empty tank with e85? If so, what other mods did he do to it? I’m just starting to read about e85 in cars not flex fuel certified, so please go easy on me. Thanks!
Yes he did. Eventually, my car was able to do the same.

You will need to purchase the CPI kit from Burger Motorsports. Even then, there's no guarantee that it will run full E85. Some cars just don't take to it well. You will also need more aggressive tuning. There are multiple options available for the platform. The only cars I'm aware of running full E85 are LAP3 cars. There may be some that are doing it with just the JB4 or the new combinations of EK1+ BEF or SXTH. I admittedly haven't been paying attention lately because I still haven't seen heard any results that show they are as fast as LAP3, so I lost interest. Also, so far LAP3 is the only tune that will let you run higher amounts of ethanol without additional fuel apparatus but it varies from car to car. I know that both Charlie and myself have been able to run E60 without CPI. Also, you're going to at least want something to log the information and JB4 is lowest cost of entry for that and pretty reliable in that department.

You'll want to keep it updated however, as they are routinely bugs/issues being found with some of the maps or features. Also, the app can freeze once in a while.

I think I may have written more than you asked for. Hope it helps some future questions you may have though.
 
Thanks for the input. I wonder if one could run 87 gas and play with e85 mix to brig octane rating up to 95 for map 3. It would be an interesting experiment. Does BMS offer a backin flash? I haven’t heard that.
I think in theory you could but your quality will be crap compared to someone that is using a higher base octane (91 or 93) than that of 87. I believe it's less timing advance and therefore, slower.
 
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Thanks for the input. I wonder if one could run 87 gas and play with e85 mix to brig octane rating up to 95 for map 3. It would be an interesting experiment. Does BMS offer a backin flash? I haven’t heard that.

I'm sure it's physically possible. However, you might push against the E40 limit a lot of cars run into. The lower your gas octane, the more E85 you need. More than E40 can cause a lot of Stingers hpfp to "crash" and lose pressure, limp mode, etc.

Start with the highest octane available (within reason) to avoid this.

Anecdotally, newer Stingers seem to handle this better.
 
Also, so far LAP3 is the only tune that will let you run higher amounts of ethanol without additional fuel apparatus but it varies from car to car. I know that both Charlie and myself have been able to run E60 without CPI.

I'm sure it's physically possible. However, you might push against the E40 limit a lot of cars run into. The lower your gas octane, the more E85 you need. More than E40 can cause a lot of Stingers hpfp to "crash" and lose pressure, limp mode, etc.
I've seen references to HFPF "crashes", but what does this look like in the logs? Is it just FP_H starting to drop from 10 to 9 or 8? "Crash" makes it sound like it plummets all at once. Any indicators you're approaching a crash?
 
I've seen references to HFPF "crashes", but what does this look like in the logs? Is it just FP_H starting to drop from 10 to 9 or 8? "Crash" makes it sound like it plummets all at once. Any indicators you're approaching a crash?
That I don't know. I've never mixed that much, just read about it. From the sounds of it, it drops drastically, not just a few percent.
 
Yes he did. Eventually, my car was able to do the same.

You will need to purchase the CPI kit from Burger Motorsports. Even then, there's no guarantee that it will run full E85. Some cars just don't take to it well. You will also need more aggressive tuning. There are multiple options available for the platform. The only cars I'm aware of running full E85 are LAP3 cars. There may be some that are doing it with just the JB4 or the new combinations of EK1+ BEF or SXTH. I admittedly haven't been paying attention lately because I still haven't seen heard any results that show they are as fast as LAP3, so I lost interest. Also, so far LAP3 is the only tune that will let you run higher amounts of ethanol without additional fuel apparatus but it varies from car to car. I know that both Charlie and myself have been able to run E60 without CPI. Also, you're going to at least want something to log the information and JB4 is lowest cost of entry for that and pretty reliable in that department.

You'll want to keep it updated however, as they are routinely bugs/issues being found with some of the maps or features. Also, the app can freeze once in a while.

I think I may have written more than you asked for. Hope it helps some future questions you may have though.

How does Lap3 run higher E w/o the need for fuel upgrades (cpi/wmi/hpfp)?
 
How does Lap3 run higher E w/o the need for fuel upgrades (cpi/wmi/hpfp)?

It can adjust fueling tables, required amount of oxygen per volume, etc.

The jb4 BEF and sxth can also do that. Just jb4 alone cannot.
 
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From interior to exterior to high performance - everything you need for your Stinger awaits you...
How does Lap3 run higher E w/o the need for fuel upgrades (cpi/wmi/hpfp)?
Simple answer is better tuning. A more technical answer is that the Lap3 tune, which comes on a seperate ecu, is able to adjust fuel bias as it sees fit in order to handle octane changes among other things.
 
It can adjust fueling tables, required amount of oxygen per volume, etc.

The jb4 BEF and sxth can also do that. Just jb4 alone cannot.
Jb4 bef can run E60 without any fuel upgrades?
 
Simple answer is better tuning. A more technical answer is that the Lap3 tune, which comes on a seperate ecu, is able to adjust fuel bias as it sees fit in order to handle octane changes among other things.
It seems to say on the Lap3 site it requires a fuel upgrade:

"LAP3 Stage 2.5 ECU Tune: 460-500RWHP (93+WMI Required)"

It seemed odd that a tune could simply overcome the physical fuel shortcomings we have on the stinger...
 
It can adjust fueling tables, required amount of oxygen per volume, etc.

The jb4 BEF and sxth can also do that. Just jb4 alone cannot.
Lap3 site says it DOES require WMI.
 
From interior to exterior to high performance - everything you need for your Stinger awaits you...
I've seen references to HFPF "crashes", but what does this look like in the logs? Is it just FP_H starting to drop from 10 to 9 or 8? "Crash" makes it sound like it plummets all at once. Any indicators you're approaching a crash?

Below is an example of when I had my pump crash while working through CPI/ ethanol issues.

The darker, bottom red line is the pump crashing. Essentially, the vehicle is not able to keep up with the fueling demand and it cuts the fuel completely. It is very abrupt once the "crash" has happened, and it feels like you hit a brick wall. Sometimes the car will cut the boost completely as a result of the crash or too many crashes. Too many crashes and you can damage your fuel injectors along with other components. It's very unhealthy for the car.

With the JB4, I believe the value for the crash is once HPFP drops under 7. Normal fueling and pump keeping up with demand would have a value of 9-10.

1000007111.webp
 
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It seems to say on the Lap3 site it requires a fuel upgrade:

"LAP3 Stage 2.5 ECU Tune: 460-500RWHP (93+WMI Required)"

It seemed odd that a tune could simply overcome the physical fuel shortcomings we have on the stinger...
So methanol is a fueling upgrade, but so is adding more ethanol or increasing the octane with race gas. Essentially, what the car needs is more available octane took take advantage of timing advance. Ethanol/CPI can be substituted for meth. So can running 100 octane race fuel.

This is also going to be a car-by-car basis. Not every Stinger/G70 with a Lap3 2.5+ tune is going to be able to just run at E60 without needing additional apparatus. It is also, not suggested to just dump E60 into the car and see if it'll run. I'm just reporting what my vehicle was able to do at that time while testing.

Tuning is just programming. Most cars can handle E20-E30 without anything additional. Most fuel has ethanol in it already. Manufacturers engineer cars to stay under the limit. They don't want liability by pushing the envelope too far. So they put in safeguards (tell the ECU to stay below certain limits) in order to extend the life of the vehicle and reduce the likelihood of something catastrophic happening. However, this limitation doesn't mean that the vehicle can't handle more power, timing, other fueling, etc. And that's why something as simple as just a tune, can dynamically change a vehicle and still be functional and good daily.
 
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Below is an example of when I had my pump crash while working through CPI/ ethanol issues.

The darker, bottom red line is the pump crashing. Essentially, the vehicle is not able to keep up with the fueling demand and it cuts the fuel completely. It is very abrupt once the "crash" has happened, and it feels like you hit a brick wall. Sometimes the car will cut the boost completely as a result of the crash or too many crashes. Too many crashes and you can damage your fuel injectors along with other components. It's very unhealthy for the car.

With the JB4, I believe the value for the crash is once HPFP drops under 7. Normal fueling and pump keeping up with demand would have a value of 9-10.

View attachment 81132
This is great, explanation + chart is really helpful. So below some threshold pressure (say 7), the car's ECU decides it's better to cut fuel entirely than run lean (or maybe risk burning out the HPFP)? And do you know if it does this by deactivating the injectors, or the HPFP? I'm assuming the latter since you say the crash is bad for injectors...
 
This is great, explanation + chart is really helpful. So below some threshold pressure (say 7), the car's ECU decides it's better to cut fuel entirely than run lean (or maybe risk burning out the HPFP)? And do you know if it does this by deactivating the injectors, or the HPFP? I'm assuming the latter since you say the crash is bad for injectors...
I can't answer about how it cuts the fuel, but yes, the car is trying to save you from having a catastrophic failure.

Another thing is that sometimes that HPFP value dropping is happening over the course of only 1-2 seconds. So, the graph may not illustrate how fast it's dropping. But the log (CSV file) is better for that. For that particular crash, the car went from a safe value (9) to crashing (7), in 1.5 secs. So as I said, it is very abrupt when it cuts. You will not like it.
 
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