New PRL e85 Flex-Fuel KIT Installed :O

NoKz

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I'll try and toss my 2 cents in and what info I've gathered as a Flex-Fuel user.

Q.) Can We Run Full E85?
A.)
Yes, you technically CAN run full E85. However, there is no benefit above an E40 (40% Ethanol) blend. Our stock fuel systems simply cannot supply the fuel fast enough with the additional ethanol. You would need to upgrade the fuel pump and injectors to get the correct amount of pressure/flow required to acquire more power.

On full E85, my top-end broke up under load because the stock fuel system was struggling to get the fuel delivered. I also saw/felt ZERO power increase over my E40 blend. The only benefits to currently running full E85 at the moment is Ease of filling up, Price and Smell. The cons are; you'll have problems on the top-end when the fuel cannot be delivered fast enough, potentially clogged injectors and lines.

Q.) What Blend Should I Run?
A.)
You'll want to run an Ethanol blend between E35 - E40. I know a lot of guys running E37. Personally, I've ran between E37 and E40 and have had zero issues. @D-RobIMW recommends E37 I believe. Dude know's what he's talking about. He's the Tuner who did @Two Step Performance 's Stage 1 and Stage 2 Tunes. And, as far as I know, hasn't thrown rods out of Sports/SI's like other tuners who say "Full E85 and lean AFR's are OK on Hondata". :rolleyes:

Q.) How Do I Calculate My Fuel Blend?
A.)
I use an Android App Called "E85 Mix Calculator Ethanol Blend". It's simple to use and helps get you very close to the mixture you want. All you need to do is;
  • Enter Your Tank Capacity (12.4 Gallons)
  • Enter Your Current Fuel Level (You'll need to guess the percentage. I've gotten really good at this. Example; Low Gas Light On = 20%)
  • Enter Ethanol Content Level (Depends On Gas Station. Mine is consistent. So I put 85.)
  • Enter Your Pump Gas Ethanol Level (Usually around 11%.)
  • Enter Target Blend Level (E35-E40)
  • Enter Current Ethanol Level (What your previous level was after filling up.)
  • Hit Calculate and get your fuel amounts needed.
Honda Civic 10th gen New PRL e85 Flex-Fuel KIT Installed :O lj3qe7jl-
Honda Civic 10th gen New PRL e85 Flex-Fuel KIT Installed :O ljauftpl-


Hey can you guys explain in depth on why our cars can't run or be tuned on Full E85 safely till we get the port injection kit? Or why tuners like Daniel from Church is tuning people on Full E and saying it's fine?
A couple of tuners, including the aforementioned one in your post, have said full E85 is fine for the 10th Gen. Results have shown otherwise. Everyone that has thrown a rod all had one thing in common: Full E85 Tune.

Phong was Tuned by Church and he now has a Window in his block. I also remember seeing 1 or 2 other similar "Blown Engine" threads and all of them were on full E85. I'm not saying the tuner is at fault or did something bad. I'm just saying, there's proof in the pudding that full E85 on a stock system not designed for it can be bad.

And also, will I be able to blend E-85 with 91 octane gas? Not sure where I can find 93 octane where I live (San jose, Ca)
You can use 91. That's all I have in my area and I've been using it for months now. Consistently on an E40 blend.
 
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IheartEg6

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I normally run an E40 blend. I got lazy and filled up on E85 one time and at the top end, the car would break up. The limitations of this fuel system are very evident. Back to E40 and everything is running beautifully.
Thx for the info i like tge blend app!!!

I use an Android app called "E85 Blend". It let's you do all the calculations and works very well. The only challenging part is guessing where your fuel level is at. I've gotten very good at it LOL. Yesterday, I was able to guestimate I was at 28% tank capacity and I nailed it spot on.
 

Chilidog

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Here is my datalog. You can see the sensor reading at 65% Ethanol (that's the winter blend they have at the pump I guess) even though I did fill up entirely on e85 Pump. They add more gasoline in winter.

Also, note I used the Hondata feature to index "Lambda" on the AF Ratio because what I've read, if you are going to use e85, the AFR is not accurate, instead we should be referring to Lambda which is post combustion and rated for whatever fuel you are using. In this case, 1.00 means you have a good A/F combustion. If you get a Lambda LESS THAN 1, I believe that means you are running RICH. If Lambda is GREATER THAN 1, you are running LEAN.

Here are a few readings, you can see the vehicle speed, RPM, Lambda, etc. I did get plenty of variances (>1, <1, when I did WOT and/or downshifts to be expected??) but you can see from the table, when I was at cruising speed, Lambda was 1.00

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Hey man — I just bought the flex fuel kit for my SI — any good install videos out there? Also, without reading this huge thread, do you still use e85?
 


 


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