My ‘85 Mustang/‘04 Cobra swap is tuned on 93 pump gas. Here in California we only have 91 octane. What is safer to run between mixing pump gas/E85 vs. pouring in some Boostane?
Mixing 91 Pump with E85 vs. Boostane etc. to achieve 93 Octane
- Thread starter Nicasio
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My local Propel station says their E85 is 100-105 octane
12 gallons of 91 octane add 2 gallons of e85 gets you 93.0 octane.
https://morepowertuning.com/pages/emix
Go down to the "advanced" 6) entry spot calculator.
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https://morepowertuning.com/pages/emix
Go down to the "advanced" 6) entry spot calculator.
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The calculator is a rough guide. E85 is ~101 octane, not 105 as pre-filled, but that's not much of concern. The real difference in knock resistance will come from heat of vaporization. Remember that octane is just one parameter of fuel that affects detonation and pre-ignition. Mixing 2 gallons of true E85 with 12 gallons of E10 91 octane would give a +1.5 octane boost and +26% HoV boost. You'll gain more knock resistance from the HoV boost than the octane boost.
Boostane, while having some effect, won't give the same results. You'll get a small octane boost and no HoV boost at a higher cost.
Boostane, while having some effect, won't give the same results. You'll get a small octane boost and no HoV boost at a higher cost.
Octane boosters tend to be expensive and don't work very well. Using E20+ in a car that wasn't designed for any ethanol might not be a great idea either, and it sounds pretty inconvenient.
Do you have a way to monitor for knock readings? The 91 may perform well enough. If not, go back to your tuner and ask for a 91 octane tune. It should be as simple as retarding the ignition timing by around 1 degree.
Do you have a way to monitor for knock readings? The 91 may perform well enough. If not, go back to your tuner and ask for a 91 octane tune. It should be as simple as retarding the ignition timing by around 1 degree.
0There’s 100+ AKI street legal unleaded race gas. I heard it’s dyed blue and some call it Smurf gas. I think that’s what this place has, where they use a blending pump for anything higher than 91. Not sure why 94, as the typical requirement is 93.
I looked it up, and there are several places in Wheatland that sell Sunoco 100 octane. They definitely have the sign, although I’m not sure how they sell it.
Maybe Rocktane Gas at the Hard Rock.
I looked it up, and there are several places in Wheatland that sell Sunoco 100 octane. They definitely have the sign, although I’m not sure how they sell it.
Maybe Rocktane Gas at the Hard Rock.
Many race tracks have street legal race gas. Not all, since a lot of race fuel is leaded and even unleaded race gas is typically sold in big drums.
Possibly this place?
https://www.allamericanspeedway.com
This place sells race gas in 5 gallon drums. Must be pretty expensive though.
https://www.ramosoil.com/company/locations/
Possibly this place?
https://www.allamericanspeedway.com
This place sells race gas in 5 gallon drums. Must be pretty expensive though.
https://www.ramosoil.com/company/locations/
Why not just buy 100 octane unleaded . 1 buy 10 gallons at a time mix 1 gallon to 3.5 for my race engine harley. Easy peasy. 240Turbo.com lists unleaded race fuel at the pump. Needs an update . there are a lot of various locations .
Safer for you is running the E85 mix. The octane boost stuff has got an interesting MSDS... That said, I do use VP Octanium in my warmed up YZ250 which should be safe in a small dosage for a couple points of octane with an emissions system. It works as my bike would ping quite a bit on 93, but with a mix to add 3 points its fine. 2.6 ounce per 10gal should get you 93 octane, and VP says that's the max mixture safe for O2 sensors/cats.
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Running and/or adding alcohol to a vehicle will require a richer fuel mixture. Most vehicles can safely run on 10% alcohol, not many can or should be run on 15% levels. You need much richer A/F ratios when running higher alcohol levels that normal old ECU's are not capable of. Don't mix higher levels of E85 to get more octane on a normal tune or ECU!
Vehicles not specifically tuned for E85 should not be running it. E85 vehicles have the tune developed for it, or an alcohol sensor in the fuel line telling the ECU to change the tune parameters. Yes, its more octane and you can certainly make a bunch more power using it if adjusting the tune for it by adding compression, timing or adding boost if running blower or turbo. E85 is worth about 35 more HP in a naturally aspirated 5.3 chevy truck engine designed with the flex-fuel option, but you can't just go running it or mixing it in a vehicle not designed for flex-fuel.
Boostane is one octane booster that actually works, and works well if you are looking for more octane. We use it in out turbocharged snowmobiles and it keeps timing from being pulled on the logs when goin up in boost levels. Not many octane boosters out there that work or work at all, but Boostane really does.
So you should only be using the Boostane if you're not tuned for more alcohol content than the normal 10% ethanol the factories design into them.
Vehicles not specifically tuned for E85 should not be running it. E85 vehicles have the tune developed for it, or an alcohol sensor in the fuel line telling the ECU to change the tune parameters. Yes, its more octane and you can certainly make a bunch more power using it if adjusting the tune for it by adding compression, timing or adding boost if running blower or turbo. E85 is worth about 35 more HP in a naturally aspirated 5.3 chevy truck engine designed with the flex-fuel option, but you can't just go running it or mixing it in a vehicle not designed for flex-fuel.
Boostane is one octane booster that actually works, and works well if you are looking for more octane. We use it in out turbocharged snowmobiles and it keeps timing from being pulled on the logs when goin up in boost levels. Not many octane boosters out there that work or work at all, but Boostane really does.
So you should only be using the Boostane if you're not tuned for more alcohol content than the normal 10% ethanol the factories design into them.
If it was mine, I would rather retune for an E30 mixture than use Boostane. I'm biased though as I love E85 and M1.
There was a relevant test to this done last year though it was comparing Boostane + 93 octane to E85. The engine was a 302ci SBF with a Vortech Si-trim supercharger, TFS TW 170cc heads, TFS1 cam, SysteMax II intake, and tuned with a Holley Terminator. It wasn't much of a contest with E85 making +42 HP and +26 TQ more than Boostane. While Boostane did allow more timing than 93 alone, it didn't allow what the engine wanted for best power, and adds nothing to HoV. Granted, we're talking about E20-30 vs Boostane, which may be more comparable in terms of knock resistance, but you're still not getting an HoV advantage with Boostane.
There was a relevant test to this done last year though it was comparing Boostane + 93 octane to E85. The engine was a 302ci SBF with a Vortech Si-trim supercharger, TFS TW 170cc heads, TFS1 cam, SysteMax II intake, and tuned with a Holley Terminator. It wasn't much of a contest with E85 making +42 HP and +26 TQ more than Boostane. While Boostane did allow more timing than 93 alone, it didn't allow what the engine wanted for best power, and adds nothing to HoV. Granted, we're talking about E20-30 vs Boostane, which may be more comparable in terms of knock resistance, but you're still not getting an HoV advantage with Boostane.
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Yes, agree as long as the OP retunes for the added ethanol, but he can't just mix it up and run it without re-tuning for that thinking he's just adding octane. If he's going to re-tune it may as well go all the way and do a full E85 tune with bigger injectors and fuel system to supply it.
I'm a lover of E85 don't get me wrong, its awesome when turned for it. Alcohol is always going to make way more power than gas & Boostane. The OP however doesn't speak about boost. Sound like he's just looking for a couple points in octane, in which case a little Boostane is cheap and easy with the existing tune already in the ECU. Blending E85 is going to run him into trouble with his existing tune.
Thank you for the replies everyone. My other question, will my car’s fuel system be safe when mixing 2.2 gallons of E85 with 7.8 gallons of 91 pump? Would it be too corrosive?
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