brutus_tx

People who have been following my Flex Fuel thread will know I've been running a Eurocharged E50 flex fuel tune for quite some time now.
Because I'm running a E50 maximum tune instead of a E85 flex tune, I have to resort to blending my fuel every time I fill up.
There are apps out there that enable me to determine how much E85 vs 93 octane I have to pump into my tank to get a nominal E50 ratio for optimum performance. For me its no big deal.
I use the apple app "E85 Mix" with great success.

For my car, to get an accurate ratio of fuel needed to achieve the E50 ratio, I need to know a few simple things:

• the amount of fuel remaining in my tank
• the ethanol content of the fuel in my tank
• the ethanol content of the fuel i wish to pump in my tank
• the final ethanol content I want in my tank.

I can read the amount of fuel remaining in the 21 gallon tank off the fuel gauge, that's simple enough.
I have to assume I have E50 in the tank because that's what I've been targeting every time I fuel up.
Using a graduated test tube I can determine what the gas station pump ethanol ratio is before putting it in my gas tank.
With all this info in hand I can use the E85 Mix app to determine how much E85 and how much 93 I need to pump into the tank to maintain a E50 ratio.

It is well known that E85 ethanol percentages can swing wildly and aren't nearly as tightly regulated as petroleum based fluids.
Fortunately for me, historically every time I tested the fuel at my local gas station it came in around the 84% mark, which is optimum.

Imagine my surprise today when I went to my local gas station on the way to Spool Performance here in Houston to install one of their soon to be released ethanol sensors in my car.
With this sensor, once installed, I'll be able to get an accurate reading of the ethanol percentage in my tank in realtime.

I rolled into the gas station with slightly under 1/4 tank.
I pulled a fluid sample from the E85 pump (there are examples on youtube) and came up with the following results.



Unfortunately for me, the tester I bought only had graduations to 80%.. I had to extrapolate and assume a reading of E70 for the fuel, indicated by the water/fuel interface clearly seen on the test tube.
The next time around, If I'm in the market, I will be sure to get one with more markings.

Using the app "E85 Mix" and going on the assumption my car already contained E50 in the tank, I used the following numbers to calculate the amount of fuel required.




I filled up using the ratios above and headed to Spool Performance.

Which brings me to the next reason for this thread.

Noting the above, the only thing I didn't readily have control over was knowing what the concentration of E85 was in my tank. I assumed I had E50 but only because I assumed I was putting the correct E50 ratio in the tank.
In conjunction, if I hadn't tested the fuel going into the tank from the gas pump I would not have known what was in the gas pump was in fact E70 and I would have ended up with fuel blend that was much less than E50. The car would have run fine, but it would have been down on power.
After seeing the test sample above it only solidified my wish to install an ethanol sensor in my car so I could accurately measure the ethanol content of my tank, eliminating the last unknown from the equation.

Spool Performance are well known in the BMW world and are just now branching across into the MB World. They have multiple products that can work across the two platforms... 2 in particular that I installed today were an inline 10 micron fuel filter and Spools Bluetooth ethanol sensor.


Spool Performance Inline 10 Micron Fuel Filter

Bits and Bobs - note the quality of the ethanol rated hoses and end fittings

Sensor Harness

Bluetooth transmitter


Inline Fuel Pump installed down stream of the fuel hard line that enters the engine bay on the drivers side of the engine bay.

Tucked behind the engine is the ethanol sensor and harness. The blue tooth transmitter is routed into the battery compartment where power is taken from a suitable source... for power I tied into the water meth controller power lead. I ran ground to the battery.

Happy days... real time ethanol readings via the Spool Performance ethanol application. E47... not bad considering I was shooting for E50 based on some assumptions.

Now before you run off to their website looking for this product, they are back ordered due to COVID-19 related supply chain issues. They are hopeful to have some units available in the next month.
Also within that time frame, they will be revamping their website to include a MB product line. One of the things they will also be offering are the hpfp's for those flex fuel users wishing to take it too the next level.
They supplied Jerry with the ones he used during beta testing of the Stage 2 E85 tune.

Now in the interest of public disclosure, I did receive a friends and family discount for this product, but it was as I was an early adopter of the system. I told them I would be posting up on MB World and they were fine with it.
Their only concern was being inundated with calls and not being able to currently fill orders, thus pissing off potential customers.

I don't know what the final price will be but I expect it will be in line with the BMW product line pricing, which is very reasonable I feel.
Also, the inline fuel filter and the ethanol sensor can be ordered separately.

http://spoolperformance.us/

Don't tell them Brett sent you...

BCP

This is awesome -- I've been looking at BT enabled Ethanol sensors for mine as well for the same reason. Good to hear they will be rolling this out along with other MB compatible products; I will certainly be looking to purchase once they are available. In regards to the Ethanol testers, I went with this one - https://www.fuel-it.com/ethanol-content-tester/

5soko

Excellent work and write up.

Another useful tool in full transparency in the name of performance!

brutus_tx

I like that tester much better!

brutus_tx

Update guys and gals!

Spool are bringing to market a handheld bluetooth enabled ethanol content analyzer to replace the bottle tester from the thread above.
It enables you to put a sample of the gas in a crucible and have it automatically determine the ethanol content of the fuel. Using the Spool Performance app it then displays the ethanol content reading.
The sensor is of the same type as the one in the car, just in handheld form.
It required less fuel to obtain a reading, which is a plus.



The unit comes with a rechargeable Lithium Ion battery.



The crucible requires only a couple of tablespoons of fuel to cover the sensor to get a reading.



With the fuel in the analyzer, the reading is almost instantaneous...




As before, if I know the amount of fuel in the tank and its ethanol percentage as read from the engine ethanol sensor.... in this case E46, I can then calculate very accurately the amount of fuel needed to obtain my E50 concentration.




according to Spool, the sensor app they have is being reworked to automatically populate the ethanol readings into a calculator function, but until this is made available I'll continue to use the E85 Mix calculator to good effect.

In full disclosure, I was given a unit to evaluate and i really like the simplicity of the system. I do not know the price for the unit but I can tell you its well made and very easy to use. Reach out to Spool Performance for more info... http://spoolperformance.us/

What fluid you do test still needs to be disposed of in accordance with state and federal regulations, but since the fuel doesn't have water added to it to get a reading, as compared to the older test tube method, you could easily put it directly into the tank.

The only real concern I have is storing the analyzer in the car in a hot Houston summer.
I'd be worried about elevated temps and a Lithium Ion battery self combusting.
The easy work around for this is to stow it in your garage and only bring it when you are going to fill up.
That mitigates that concern, for me at least.

maxusa

I appreciate your pushing the Ethanol envelope. It is service to the community. I am following with great interest and learn a lot in the process. I do want to ask, however, your opinion about the practicality of testing and mixing fuel. Is this for mass adoption? Should this mature to some level to become practical?

brutus_tx

This is not geared towards the enthusiast who appreciates a fast car but doesn't understand the mechanics behind it.
For those of us that are on the "spectrum" as I prefer to call us, blending some 93 and E85 to achieve optimum performance is a no-brainer. We do it without giving it a second thought.
For those people who want to set it and forget it, they are better off getting a tune that doesn't rely on blending fuels to achieve their performance goals.

Stage 2 E85 tunes are in the final stages of development/testing and will be hitting the streets sometime in the next few months I believe.
For those with pockets deep enough to shell out the money required to purchase the aftermarket fueling required, they will have an avenue whereby they will be able to roll up to a gas station and pump a tank of E85 and net 10's all day.
We're not there yet as far as maximizing the cars potential.
Those of us who want the maximum available performance with stock hardware have to resort to blending fuels currently. E50 seems to be the happy medium between the more aggressive E tune and the cars stock hardware.

There is an EC Stage 1 E85 tune on the market which gives you the ability to just pump E85, but it is less aggressive than the tune most of us are running. Those of us who are trying to eek every ounce of performance in search of that fastest time will always opt for the E50 tune and put up with blending fuel in the interim until the Stage 2 offering is on the market. Once the stage 2 offering hits the consumer market I'm sure there will be a mass exodus of the more manic among us, while others will continue as they are currently doing. The majority of people running the E50 tune are now in the 10's and some are content with that.

Mhoughland

I just installed this same kit I’m my 2015 e63 and honestly my kit seems a little different. I didn’t get instructions so I tried to use your pics as a cheat sheet, but it would work. I ended up with my filter where your sensor is and the sensor where your filter is. Either way it ended up working. should have the e50 tune this week and I’ll post impressions. I wanted to get the HPFP spool offers and run e85 but I honestly can’t see the lift pump keeping up so I decided to wait until more research is in. Overall the kit from spool is quality.

nota_amg