Its funny I just did my thread on this. e30 is safe to run for sure. I would not push the fuel trims as far with e50. Doesnt sound like a big jump, but it is in fuel volume demand. Being a Ford tuner myself, I can say that any benefit you are getting from e50, you've already gotten from e30. There is a spark adder ceiling, I'm not sure what it is with these cars, but at some point you are pushing the fuel trims farther than necessary for no gain in spark or extra knock protection.

My advice would be stick with e30. You are getting the equivalent of 96+ octane for the stock tune that is likely set up for 91+. Once you hit that octane spark adder ceiling, then you are just pushing the fuel system for no more gain. At e30 you wont be getting any knock whatsoever from the stock tune anyway.

If you want to run e50, then you should just be running full E85. Get the tune, run the flex sensor(or not), and just tune for full E. Flex is nice especially when you can run a real E sensor that can feed into the PCM for correct fueling and spark demand changes. But for inferred flex (no sensor), its just better to run a straight up E tune set for 9.80 stoich so you can lock in all the spark the car wants.

Personally Im going to run e30 going forward on the stock tune (93/E85 mix), until Im ready to unlock it and switch over to full E85.

Also remember if you run E30, you need to account for the extra E in the tank for the next tank if you are not running it down to 0 before you refuel. I dont ever let my cars get near empty, so I have to use an Ecal app to calculate the current and desired E content so I can offset whats in the tank so im not upping the E content on every refuel.

First e10-e30 tank was 4.93 gallons of E85 and then top off with 93. After that, its variable how much E needs to go in before you top it off with 93 depending on how much fuel is left in the tank. Lots of free app calculators for this on the app stores.

 

I want to run this for my next pass at the dragstrip but was considering 1/2 tank mix. Wouldn’t it be better to show up ready to race 60lbs lighter? I wouldn’t care on the way home if I topped it up with 93 octain and lost the advantage after Im done.

 

Thanks for posting, our E85 stations are only E65 to E67. My 16 C7 (bolt ons) and 22 Camaro with 2300 Maggie and TooHighPsi port both ran on E65 all the time, I even ran E50 (winter blend) in the winter here in Missouri. Each time I filled up or added to each tank I logged it with HP tuners. I can't log the C8 without a FF sensor. I'm starting my FF today. I'll be down to about 2 gallons when I fill up with E65 and 93 today. When I worked for Magnuson we had to send all our canned tunes out with 91 octane fueling and timing tables. We ran multiple E content on my 16 C7 and found no gains with a bolt on car past E65, we probably made 30 to 40 pulls on the dyno and dozens of passes at the drag strip and no gains past E67. We also tried C85 and just wasn't worth the costs to buy it.

 

Absolutely, just add 2.5 gallons of pump E85 to a 1/4 tank of 93 pump and then carefully add 93 to bring fuel level to half tank. Then burn this mixture going to the track and allow some self tuning and burn off a few gallons to be even lighter.

 

Our E30 is mixed with 87 octane and comes out to 93 octane according to the state of Missouri person I talked to that takes samples of each station in Missouri.

 

My 2024 had an empty tank and I started to add my usual ~3-4 gallons of E85 before filling the rest with 93. The E85 pump was running at about 0.01 gallons per second so after some minutes I went inside to tell them. When I came out, I had a full tank of E85.

I very gently left the station and continued to work quite gingerly, fully expecting a check engine light due to lean condition. I gradually exposed more fuel trim cells, giving ST and LT time to adjust. By the next day, I was at WOT with no apparent issue and no check engine light. Shocked again! I wish I had the time to connect a scanner to see what the trims were at, but I am sure they would have been huge.

Of course, what is labeled as E85 is not always really E85, but at least based on the extreme decrease in MPG, I would estimate that it was really E85 or close to it.

 

That was my thread, E50 and Mike Sitar that owns TooHighPsi has run E50 without a check engine light. However, when he started exceeding that he did get a light. He did get the ECU unlocked and has now tuned it for full E85 which many stations in California have now. As I've posted out stations in Mid Missouri are selling E65 to E67. I may try some E65 with the E30 and maybe get close to E40 and see if that works. Thanks for the info and keep us up to date. My mileage dropped about 3-4 mpg on E30.

 

Pump E85 usually tests around E65 - E68, did you do any WOT pulls ? did you feel more power?

 

He did say he was at WOT the next day.

 

Well I thought it over since you accidently tried E85 or less. I'm at about 3/4 tank of E30 from the pump, I've just got to try and add the E65 to fill it up today. I will do as you did and take it easy on my drive home which is about 25 miles. Fingers crossed and if I don't get a light I'll hammer down tomorrow

 

Yeah, he did say that. One needs to do multiple WOT pulls and allow automatic redline shifts a few times to do its own tuning imo. I also would hope you would feel the difference during those WOT tests.

 

Totally agree.

 

The car is still relatively new to me, though I would say no obvious power gain, but no knock retard in extreme heat. I don't know the PCM program, but I am sure you need a timing table change to get much gain from the E85. I would expect it to be more consistent without the knock retard variable coming into play.

 

Im leaning that was as well into the consistency theory. That would be a given in my opinion. Which is nice for bracket racing.

I believe there are high and low octane tables as well that you might be able to get into.

 

High is likely associated with ~91/93, and low with ~87/89. If you don't have good gas in your area, I am sure the E85 blend is a greater benefit.

I have 93 everywhere, but even with that, all my prior vehicles could experience some knock retard in extreme Texas heat.

Are you scanning an unlocked PCM with HP tuners? They said "you can attempt to use scanner without an ECM upgrade service however, you may be limited to very basic PIDs."

 

Tweaker, are you logging with HPT Mpvi 2 or 3? I'm going to plug in with my Mpvi 2 and see if it will read the fuel trims. I'd like to continue to add more E above the 30 at some point. Are you still on the E85 tank or have you added in some 93/10?

 

I quickly ran out the tank of E85 with no issues (with at least a 25% MPG decrease). I now have a tank of 50% 93 and 50% E85.

I want to order an MPVI3, but I am not going to buy 8 credits and unlock my PCM just to see the trim cells and knock retard table. The message from HPT was discouraging, but I may still try one from Amazon just to see what I can observe.

 

So today I was in the area that I get myE. I probably needed about 5 to 6 gallons to be back on full. I decided to up the ante to add some E85 to my E30. So, I added 2.5 gallons on E65 which is was we get in our area. Then I added E30 which is what is we also get at the pump. No check engine lights. However, I didn't get on it, tomorrow I'll let it eat. My mpg in a 40 mile trip was 24 mpg, with 93/10 it was averaging about 27 to 28 on the hwy. However I'm saving almost a dollar a gallon every fill up. I rather smell honey with E85 than nasty *** with 93/10, What would you pick?

 

I have Mpvi2, I'm going to see if it will log and see where my fuel trims are. I'm not spending what they want to unlock the Ecu, I'm just going to do some other upgrades to go along with my E30 plus. I may pull the Lt2 intake and TB and have them ported or just buy an Lt2 and Ported TB.

 

E should get you worse fuel milage. you use more of it.