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Let’s talk E30 in the stock 5,0

ChitownStang

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So I’ve been doing a bunch of reading lately on adding “E85” to 93 octane gas to achieve a blend around E30. It’s really simple math in a calculator I linked below. if you know what % ethenol your 93 is and what percent ethanol your E85 is. Most 93 is 10% and my specific area has 70% E85 gas.
Lots of people report it’s safe on these gen 3 + 5.0’s and yields some decent mid-range hp/tq
I came from a 21 Mach 1 with a Wengerd Flex fuel tune and had no issues running E70 all summer for years with stock fuel system.
So, since we have no tune options yet and this gen 4 Coyote has been around for 1.5 years now, is this a safe thing to do for some extra power??
https://www.getmtuned.com/ethanol-fuel-mixture-calculator
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goodlettjr

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I fill mine up (guesstimated) with E30. Currently have it in there now. No check engine lights. It sounds a bit different, may be some seat of the pants dyno improvement but I really don’t have any idea. There are a few running it on the track and improving 1/4 mile times.

I use a couple of apps (iPhone)

E85cal - helps me get close on the mixture while on the go

Alt fuel - to find fuel
 

Alan Applegate

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There are several reasons upping the percentage of ethanol over the factory spec (E85) isn't a good idea. Here's one...

To properly run high levels of ethanol requires major changes to the fuel system including injectors and higher flow fuel pumps.
 
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ChitownStang

ChitownStang

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There are several reasons upping the percentage of ethanol over the factory spec (E85) isn't a good idea. Here's one...

To properly run high levels of ethanol requires major changes to the fuel system including injectors and higher flow fuel pumps.
This is not true. Ever since gen 3 coyote was released in 2018 it has the fuel system capable of running E without changing injectors.
12:1 compression and Direct Injection/ Port injection.
I did NO fuel system changes in my Mach 1
 


Q6543

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It’s safe, E30… especially N/A will just make sure your car sees MBT in the factory tune.
You could do logs and see if the 93 in your area allows for full spark if you want but either way

and stoich on E30 isn’t an issue at all, widebands will trim in the extra fuel

so much bad information about ethanol and running blends
People saying “tune is needed “ don’t understand the car IS tuned to add in timing and 93 octane is barely adequate N/A… as seen by people doing logs and not getting full spark

I’ve been on E30 since day 1 basically
 

Germansheperd

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Depending where you live, temperature, what time of year, blend of gas sometimes your car can pull timing on 91/93.
E30 will just make sure you get everything your car has and may even pick up a couple hp.
A tune will net you the most.
 
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ChitownStang

ChitownStang

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Just keep an eye on your short term fuel trims
Can you explain this better, are you saying g to watch my A/F gauge.
What should the safe range be at when on the accelerator to off acceleration?
 

robvas

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Can you explain this better, are you saying g to watch my A/F gauge.
What should the safe range be at when on the accelerator to off acceleration?
Forget the gauge, log/view your short term fuel trims and AFR/lambda in real time

Normally would want the AFR/LAMBDA to be in the .9's in a NA car at wide open throttle

If your short term trims are going well into the 1.1x or 1.2x range you might be having trouble keeping up with the extra fuel needed

Log a couple runs on plain old 93 to see what's normal for your car
 

drive_55_not

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Can you explain this better, are you saying g to watch my A/F gauge.
What should the safe range be at when on the accelerator to off acceleration?

Ford presumes the fuel you are using is an E10 blend, So they use 14.1 as the default A/F ratio.

Here's where it gets tricky, The tune is looking for 1.0 Lambda part throttle and .82 Lambda WOT ...

Regardless of what ethanol content is in the tank, The displayed A/F ratio is going to read like it has E10. The dash will show 14 part throttle and 11.6 WOT.

As far STFT and LTFT's .. I run a E40 blend and FT's add 15%.

I have logged where one bank will start adding more fuel than the other, Not sure why that happens, but I started doing a KAM reset and that keeps the trims the same.


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If you wanna run ethanol I would suggest installing an ethanol guage/ sensor. This will allow you to monitor the amount in your car so that you dont accidentally run to high of a percentage and throw your car into limp mode. The calculators are nice but I found there are always variables that the calculator alone may not account for.
 
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ChitownStang

ChitownStang

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Thanks for the info guys. Logging may be above my pay grade and not really worth the squeeze for me.
I was just looking for a safe way to get a little more throttle response like I had in my tuned Mach.
Back on a factory tune after 2 Tuned mustangs for last 10 years kinda sucks! Lol
Running E70 on flex tune was such a noticeable difference
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