E50 without a tune
Instructor
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From: South FL (Fort Lauderdale)
Melting Slicks
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From: Early 2020 Z51 Coupe, Original Owner, Ahwatukee Foothills, AZ
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From: Albuquerque NM
Has anyone dyno'd their car with and without running E-30?
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Melting Slicks
Joined: Oct 2009
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From: Moberly, Mo
I have a reliable source that was running his at E50 without any issues. He's unlocked his ECU so they can build a turbo system for it and Port Plates for the IM. He told me I should be fine at E40 so I'm going to start there, and it I get a check engine light I'll add some 93 to it. We have E30 at our pumps so I'll figure a formula each time when I fill up to get it to E whatever it will tolerate without an issue. He didn't make much more power running higher E contents after they were able to tune it, he changed the stoich. Additional timing made no more power either, I believe he said that total was already at 26 degrees. We used to run 28 degrees pm on my C7 on E65.
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Melting Slicks
Joined: Oct 2009
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From: Moberly, Mo
My local stations have E15, E30 and E85. I'll try the E30 first once I get down to about 1/8 tank, we have 10 percent in all our fuel in Missouri. Some stations have 91 with no Ethanol also.
Melting Slicks
Joined: Nov 2012
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From: SUFFIELD CONNECTICUT
This formula from a Forum member a few years ago. 5 gallons pump E85 to 13 gallons (18 gallons is full tank) of 93 which has ethanol in it. I personally mixed 2.5 gallons pump E85 to 6.5 gallons of 93 (9 gallons is a 1/2 tank ) It works, you can feel it by the seat of your pants. I drive to the track with the mixture and do some wot pulls and allow redline shifts while in drive to let the car self tune during my journey up to the track.
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Melting Slicks
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From: SUFFIELD CONNECTICUT
I do not believe E30 from the pump is a mixture of E85 with 93 octane pump. The formula that was used was mixed with 93 pump or the minimum 91 octane. The mixture is E30 and not mixed with 87 or 89 low octane. The C8 loves it and tunes itself nicely to it. Zero issues.
Melting Slicks
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From: SUFFIELD CONNECTICUT
Le Mans Master
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From: Omaha
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Correct, pump E30 is not the same as mixing 93 and E85. General pump E30 is only equivalent to 93 octane (minimum) usually done by mixing "regular" (87, or even 85 in some cases) and E85 (unless you are getting Sunoco E30-R). Plus, you have to take into account any 91/93 left in your tank, and that the E30 mix at the pump relies on the E85 part of the mix truly being 85% E, which it never is (typically E85 is 60-70% E for summer blend). In "E" fuels the number is max % of ethanol, not the guaranteed %. To really get an E30 mix, you need to test the E% with a test kit, and then use a calculator (there are quite a few online) to figure out how much E85 and 93 you need to get a true 30% E mix. I think one reason some may be reporting running 40% or even 50% E is because they are assuming pump E85 is actually 85% E.
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Melting Slicks
Joined: Oct 2009
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From: Moberly, Mo
I have Mpvi2 and I'm going to upgrade to Mpvi3 so I can log the E content once I figure out where I need to be each time. I've run E85 in my last three cars that I drag raced and you are right, when I logged content after every time I put fuel in it was consistently around 65 to 68, I have seen KCMO and St Louis in the mid 70s but never any higher than that, plus all the dyno and drag passes I made we never saw any gains above that E70 number. I've run C85 and E85 Vp with no advantage over pump E65. My cars have made from 477/485 on my bolt on C7 to 707/685 on my 2022 Camaro with a 2300 Maggie and Thpsi injection all the way up to 850 plus on my 16 Camaro with a Maggie 2650 for a forged bottom end. I've got over 220 dyno pulls on all three cars total and close to 450 passes down the track between. All on E65, so you info really helps me out since I've never had to mix anything like I'll have to now. Thanks
Le Mans Master
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From: Omaha
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From: Albuquerque NM
Le Mans Master
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From: Omaha
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Melting Slicks
Joined: Nov 2012
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From: SUFFIELD CONNECTICUT
I have Mpvi2 and I'm going to upgrade to Mpvi3 so I can log the E content once I figure out where I need to be each time. I've run E85 in my last three cars that I drag raced and you are right, when I logged content after every time I put fuel in it was consistently around 65 to 68, I have seen KCMO and St Louis in the mid 70s but never any higher than that, plus all the dyno and drag passes I made we never saw any gains above that E70 number. I've run C85 and E85 Vp with no advantage over pump E65. My cars have made from 477/485 on my bolt on C7 to 707/685 on my 2022 Camaro with a 2300 Maggie and Thpsi injection all the way up to 850 plus on my 16 Camaro with a Maggie 2650 for a forged bottom end. I've got over 220 dyno pulls on all three cars total and close to 450 passes down the track between. All on E65, so you info really helps me out since I've never had to mix anything like I'll have to now. Thanks
Melting Slicks
Joined: Nov 2012
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From: SUFFIELD CONNECTICUT
Thread Starter
Melting Slicks
Joined: Oct 2009
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From: Moberly, Mo
Yes sir, very aware of that. HP tuners wants 1499.00 for the unlock, 8 credits, flex fuel sensor is around 350 (dsx) plus the tune. I've been tuning with HP tuners for over 10 years, above 30 percent is not worth the money to me for 40 hp. Now, if was going to do other mods such as a SC I'd have no choice. I'd be happy with E30, cheaper to purchase and addition power is never bad. I will still probably buy MPVI3 so I can at least log the E content to make sure I'm keeping it around 30 percent.
Last edited by 99vetteran; Oct 7, 2025 at 08:51 AM.