1. What is E85 Fuel?

E85 is a fuel blend containing 51% to 83% ethanol mixed with gasoline. It's called "flex fuel" because it can be used in flexible fuel vehicles designed to run on gasoline, ethanol, or any mixture of both.

2. How Does the Calculator Work?

The calculator uses the E85 HP gain formula:

Where:

• \( HP_{gas} \) — Horsepower on gasoline (HP)
• 1.1 — 10% average power increase multiplier

Explanation: The equation estimates the approximate horsepower gain when switching from gasoline to E85 fuel, accounting for ethanol's higher octane rating and cooling properties.

3. Importance of HP Calculation

Details: Understanding potential power gains helps enthusiasts and racers evaluate whether converting to E85 is worthwhile for their application.

4. Using the Calculator

Tips: Enter your current horsepower on gasoline. The value must be valid (greater than 0).

5. Frequently Asked Questions (FAQ)

Q1: Why does E85 provide more power?
A: E85 has higher octane (100-105) allowing more aggressive timing and boost, plus its cooling effect increases charge density.

Q2: Is the 10% gain accurate for all engines?
A: No, gains vary (5-20%) based on engine tuning, compression ratio, and forced induction. Turbo/supercharged engines typically benefit most.

Q3: What are the drawbacks of E85?
A: Lower energy content means ~30% worse fuel economy. Requires compatible fuel system components and more frequent refueling.

Q4: Can any car use E85?
A: Only flex-fuel vehicles or those specifically converted with appropriate fuel system upgrades.

Q5: Does E85 require special tuning?
A: Yes, optimal performance requires adjusting air/fuel ratios, ignition timing, and often larger fuel injectors/pump.