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So I decided to try running a conservative e85 mix with 93 shell v power (10% ethanol). The reason was not as much for power but to see if I could lean the car out a little as I have joe z exhaust, Headers, And takeda intake. I did this mix with half a tank of 93 octane (7 gallons) w/ e85 (1 gallon). This mix make e19 which has about 95 octane with my ratios etc.
The results... I have not hooked my car up to a dyno or a obd2 to monitor the status AFR this is just purely off of feel and what I am diagnosing based off rpm movement or what have you. I do notice that my car runs a lot less rich. The rpm does not bog down as much, the rpm move a lot more freely based on my comparison. I also notice I am getting peak torque I would say 500 rpm higher. Over time I am not sure if the computer will counter this mix or not. I also an getting less back firing in the pipes when I let off. I do not get any knocking as of now. But I will keep monitoring to see if I potentially get small gain or just can lean my car out a bit.
I just did data logging with RR-Racing with 6 gal 93 and 2 gal 100.
There was no change in timing.
I am not running it for octane boosting/power gains I am running e85 in it to see if it leans it out a bit. Running e85 is different than putting in high octane fuel. I assume the car will tune it out anyways but just trying it to see if I notice anything.
I am not running it for octane boosting/power gains I am running e85 in it to see if it leans it out a bit. Running e85 is different than putting in high octane fuel. I assume the car will tune it out anyways but just trying it to see if I notice anything.
It might, but the wideband planar O2 sensor is looking for a specific lambda from a table in the ECM, and the lambda for ethanol is different than gasoline, so it might just stick. The only thing to be careful about is not exceeding 10% ethanol. Lexus is very specific about this in the owner's manual (at least in 2008), and I am certain it has more to do with the type of seals they used and how they will deteriorate if you use too much alcohol.
yea typically higher ethanol fuels (higher than 10%) can eat away at seals and gaskets along with the fuel injectors and fuel pump not being able to handle this. I wouldnt mess around with adding any e85 to a car not meant for it.
Using the knowledge I gained from my Suby tuning days, I would expect the ecu will likely adjust over the long term - on most modern motors the ECU is always trying to maintain stoich (14.7 AFR for gas) at idle and something richer than stoich on the highend of the rev band. When you add in ethenol you are essentially leaning out the mixture to something leaner than stoich.
The ECU will sense a lean AFR reading at idle and trim (add in this case) enough fuel to get it as close to stoich as possible. That trim % is then applied to the entire rev band to make sure you do not lean too far out on the high end of the rev band. I would expect the ECU to eventually trim the AFR to stoich by adding some percentage of fuel throughout the rev band. This will basically kill the performance gained you felt when you first added the E85.
I wonder if the 10% ethenol cap is a result of protecting from seal deterioration or if it is in place because if you add more than 10% ethenol, the injectors will struggle to add enough fuel to hit the target AFR on the top end of the rev band?
Most cars tell you not to exceed 10% ethanol. It will be fine running it for short periods of time. Just don't let it sit in the car. I ripped through more than a quarter tank this morning. Haha. The torque definitely shifts a little higher up.
It's odd that more torque is being noticed up in the higher rpms because typically ethanol will increase power across with the board, especially in the lower rpms. At least on turbo cars that's the effect.
To really take advantage of ethanol, you need to be able to crank up the timing, typically in the 5 to 7 degree range above stock. That's likely well out of the range of the stock timing tables. Without being to get in and reprogram the timing tables, you're likely not going to see squat for gains over using a quality 93 octane fuel.
Running E60-E85 on an NA motor (with tuning) typically nets about 3%-5% in HP/TQ. On a turbo car? Around 10-15%. On a turbo car and if you're not careful, ethanol is a superb way to wreck a motor because ethanol can generate so much more low end power. If you're not careful with the detonation and/or air/fuel ratio control, it will snap/bend a rod, spin a rod bearing, or crush a piston ringland.
So I put some E85 and did some logging and the car work well. I did 3 pulls on 93oct back to back, on the first pull I forgot to turn off the AC. Then I went and got some E85 and did 3 pulls back to back. The interest thing is that the car makes peak torque later in the rpm than on just 93oct. For some reason on the last 93oct the car applied about 1.5° less of timing; maybe it was because of heat soak but the intake temp and coolant temp were the same as the other passes. Another interesting thing is that with the extra E85 the car leans out through most of the rpm range but at redline it goes to the same AFR as on 93oct.
Running e85 and vpower 93 octane
