An exhaust header is a performance-minded replacement for the stock manifold. Instead of dumping all cylinders into a shared chamber, it gives each cylinder its own smoothly curved tube of equal length. This design uses the momentum of departing gas to help scavenge the next cylinder, improving how well the engine breathes.
Animated: how a Exhaust Header actually works
🔧 How It Works, Step by Step
1
Valves release gas
Each exhaust valve opens and sends a pulse of gas into its own tube.
2
Tubes stay separate
Long, equal-length tubes keep the pulses from interfering with each other.
3
Scavenging occurs
A departing pulse creates suction that helps pull exhaust from the next cylinder.
4
Tubes merge
The runners join at a collector timed to keep flow moving smoothly.
5
Breathing improves
Reduced backpressure lets the engine make more power, especially at higher RPM.
🧩 The Key Parts
Primary tubes
Equal-length runners that carry each cylinder's exhaust separately.
Collector
Merges the tubes at a tuned point to aid scavenging.
Head flange
Bolts the header to the cylinder head with a gasket.
Merge or O2 bung
Provides a spot for the oxygen sensor and clean merging.
📋 Free OBD2 Code Cheat Sheet
The 50 most common check engine codes with likely cause and DIY fix cost. Sent once.
🩺 Signs of a Failing Exhaust Header
Ticking that grows with RPM
Loss of low-end torque if poorly matched
Exhaust smell in the engine bay
Check engine light from a leak
Loud raspy exhaust note
Failed emissions if catless
⚠️ Common Problems
Gasket leaks
Thin header flanges can warp and leak at the head, causing ticking and skewed sensor readings.
Cracking
Thin-wall tubing cracks from heat and vibration, especially at the welds.
Poor fitment
A header that does not match the engine can hurt low-end torque and cause leaks.
💰 Cost to Fix
$300-$1500typical range to repair or replace, parts and labor
❓ FAQ
What is the difference between a header and a manifold?
A manifold is a compact cast part that prioritizes durability and quiet, while a header uses tuned tubes to improve flow and power.
Will headers void my warranty?
Emissions-related mods can affect warranty coverage on related parts. Check local law and use CARB-compliant headers where required.
Do headers really add power?
They can, especially at higher RPM on a modified engine. Gains are smaller on a stock engine and depend on tuning.