Exhaust Header for Jeep Wrangler (1991-2002) 2.5L

High-Flow Replacement Exhaust Header for 1991-2002 Jeep Wrangler

What it Does: The Exhaust Header replaces the restrictive, crack-prone factory manifold on the 1991-2002 Jeep Wrangler to reduce exhaust backpressure, accelerate gas velocity, and restore lost engine torque.

The Stock Jeep Wrangler Manifold Stress Fractures

The factory exhaust manifold on the AMC 150 2.5L inline-four engine is notorious for severe thermal fatigue. Constant thermal cycling between low-speed rock crawling and highway loads induces extreme stress at the runner junctions and collector welds. This causes microscopic fissures that propagate into severe exhaust leaks, causing unmetered oxygen ingress, skewed upstream O2 sensor readings, erratic idle fueling, and distinctive ticking under acceleration.

The Engineering Solution

Fabricated from heavy-gauge mild steel, this direct-fit replacement header incorporates smooth, mandrel-bent primary tubes designed to balance scavenging dynamics across all four cylinders. Precision-machined, thick-gauge mounting flanges resist thermal warpage to eliminate flange-face blowouts against the cylinder head. The integrated collector smoothly funnels exhaust pulses into the downpipe, lowering combustion chamber heat soak and eliminating the structural failure points inherent to the OEM cast and welded log assemblies.

Technical Specifications

Compatibility

• 1991-1995 Jeep Wrangler YJ 2.5L 4-Cylinder
• 1997-2002 Jeep Wrangler TJ 2.5L 4-Cylinder

Frequently Asked Questions

Does this fit the YJ and TJ Wrangler?
Yes, this is a direct bolt-on replacement for both the YJ and TJ generations equipped with the 2.5L AMC 150 engine.

Will this require custom ECM tuning or cause a Check Engine Light?
No ECM recalibration is necessary, and factory oxygen sensor locations are retained to ensure correct closed-loop air-fuel ratios without throwing diagnostic trouble codes.

The Jeep Trail Durability Standard

Trail rigs require uncompromising mechanical reliability under heavy load and extreme chassis articulation. This header delivers structural stability designed to withstand trail washboards, off-camber heat loads, and rocky climbs without cracking or blowing exhaust gaskets.