1. What is a Boost to Horsepower Calculator?

Definition: This calculator estimates engine horsepower by incorporating the effects of boost pressure on torque output.

Purpose: It helps automotive enthusiasts and professionals understand how forced induction (turbocharging/supercharging) affects engine power output.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( HP \) — Horsepower
• \( T \) — Torque (lb-ft), adjusted for boost pressure
• \( RPM \) — Engine speed (revolutions per minute)

Boost Adjustment: Torque is increased by approximately 1% for every 0.147 psi of boost (simplified atmospheric pressure relationship).

3. Importance of Boost-Adjusted HP Calculation

Details: Understanding boost effects helps in engine tuning, component selection, and performance prediction for forced induction systems.

4. Using the Calculator

Tips: Enter base torque (without boost), engine RPM, and boost pressure in psi. All values must be ≥ 0 (boost can be 0 for naturally aspirated).

5. Frequently Asked Questions (FAQ)

Q1: Why 5252 in the formula?
A: This constant comes from the relationship between rotational speed and power, where HP and torque curves always cross at 5252 RPM.

Q2: How accurate is the boost adjustment?
A: This is a simplified estimate. Actual gains depend on engine efficiency, intercooling, and other factors.

Q3: What's a typical boost pressure?
A: Street cars often run 6-15 psi, while performance builds may use 20-30+ psi.

Q4: Does this account for turbo lag?
A: No, this calculates peak power at specified RPM assuming full boost.

Q5: Can I use this for superchargers?
A: Yes, the calculation works similarly for any positive intake pressure.