FUEL GUIDE

Bavarian Tuning Solutions Fuel Guide

When transitioning from a lower octane fuel to a higher octane fuel, it’s crucial to ensure the engine’s safety. This is particularly important when moving from a lower octane to Ethanol or Race Fuel. Utilizing Ethanol and Race Fuel maps with lower-grade fuel can lead to damage to spark plugs and potentially the engine. Please adhere to these guidelines when switching fuels:

1. Empty the gas tank completely.
2. Allow the engine to idle until it stalls out.
3. Refill the tank with the higher octane fuel.
4. Drive lightly for approximately 15 miles. There may still be remnants of lower octane fuel in the fuel lines, especially for dual injection vehicles. If transitioning to Ethanol, you might encounter a fault for fuel trims being out of range. In such cases, clear the fault code, switch to the ethanol map, and continue driving lightly.
5. Switch to the higher octane map and drive lightly for 5 miles before accelerating to full throttle.
6. If you notice any hesitation, timing issues, audible knocking, or other abnormal signs, ease off the throttle immediately. Lower quality fuel might still be present in the lines. Repeat the aforementioned steps if necessary.

Octane Levels & Programs

Never use an octane level lower than what’s recommended by the tune. For instance, avoid using 91 Octane with a 93 Octane tune. However, using a higher octane than prescribed by the tune is acceptable. For example, running 93 Octane on a 91 Octane program is permissible and may even enhance performance in certain scenarios.

Race Fuel Information

Bavarian Tuning Solutions advises using Sunoco GT260 for 100 Octane tunes and Sunoco GT260+ for 104 Octane tunes, unless stated otherwise. Only utilize the recommended fuels as other types may not be compatible.

Ethanol Information

Ethanol content can vary significantly. Fuel labeled as E85 may contain anywhere from 85% to 51% ethanol, depending on location and season in the USA. Similar variations can occur outside the USA due to ethanol laws. Most non-flex fuel E85 may only operate within the range of E60-E85. Always verify the operating range on our product pages or by contacting Bavarian Tuning Solutions. Using ethanol content lower or higher than specified for the map may lead to issues such as knocking or fuel trim problems. It’s important to note that Bavarian Tuning Solutions’ tunes for regular gasoline are not designed for ethanol. However, ethanol is commonly blended with gasoline at the pump. As long as fuel trims and the fueling system are not maxed out, this is typically acceptable unless otherwise specified.

Octane Booster

Avoid using octane booster as it may not provide any benefit or could potentially cause other issues.

Leaded Fuel

Do not use leaded fuel as it can damage your oxygen sensors.

Water/Methanol

The use of water/methanol may have adverse effects, especially when used with higher octane maps and lower octane fuel. Usage is at the discretion of the end user.

Nitrous Oxide

Similar to water/methanol, nitrous oxide may also have adverse effects. Its usage is at the discretion of the end user.

Accidental Use of Low-Quality Fuel

If lower quality fuel is accidentally used, it’s recommended to drain the tank. However, if you’re running a higher pump fuel program and only have access to lower octane fuel (e.g., using 93 Octane program with only 91 Octane available), proceed with caution. Avoid aggressive driving, particularly with boosted engines. Maintain low IAT and throttle input. Be vigilant for signs of knocking and discontinue driving if detected.

Rough AKI to RON Conversion Guide

Please note that this guide provides a rough estimate only, as many factors contribute to octane levels:

– 87 AKI = 91 RON
– 91 AKI = 93 RON
– 93 AKI = 98 RON
– 100 AKI = 104 RON
– 104 AKI = 108 RON

Terminology

In the E85 designation, “E” stands for Ethanol, and “85” represents the percentage of Ethanol in the fuel. In the North American Region (NAR), octane levels are described using the Anti-Knock Index (AKI), (RON+MON)/2, or (R+M)/2. On the other hand, the Rest of the World (ROW) uses RON (Research Octane Number) when referring to octane levels. RON is the Research Octane Number, and MON is the Motor Octane Number.