Acura Integra DE4 R1-Spec Catback Install Tips

By REMARK Exhaust | Published: 2026-10-28

Category: How-to Guides

Step-by-step guidance for installing the R1-Spec catback on your 2023+ Acura Integra DE4, including common mistakes and checkpoints to ensure a clean fit.

Quick answer

Install the R1-Spec catback on your Acura Integra DE4 by following a careful sequence: prep, remove the factory system, test-fit the new components, and torque everything in the right order. Pay special attention to hanger alignment and tip positioning to avoid rattles and misalignment.

Why the R1-Spec catback is a good DIY project

The R1-Spec catback is designed with a high-flow layout and minimal bends, which makes it lighter and simpler to install than systems with complex routing. Because it uses a 2.5" diameter from the first joint onward, the components align in a straightforward manner, but you still need to be methodical.

One common challenge is that the factory exhaust hangers can be stubborn, especially on a newer car. Using a rubber lubricant and a gentle twisting motion helps avoid tearing the hangers. Another point to watch is the tip alignment: the single exit muffler should sit centered in the bumper cutout, so you may need to loosen the clamps and adjust before final tightening.

Installation steps

Prep the car and gather tools: Park on a level surface, chock the rear wheels, and raise the rear with jack stands. You'll need a 12mm socket, 14mm socket, penetrating oil, a rubber mallet, and a torque wrench. Spray the factory hangers and bolts with penetrating oil and let them soak for 10 minutes. Never rely on a floor jack alone; always use jack stands.
Remove the factory catback: Starting from the rear, unbolt the muffler hangers and the mid-pipe connections. Use a twisting motion to pull the hangers off the rubber mounts. Lower the factory system carefully, as it may be heavier than expected. If a hanger tears, replace it with a new one before installing the new system.
Test-fit the R1-Spec components: Before tightening anything, hang the new mid-pipe and muffler loosely. Slide the clamps over the joints but do not tighten. Check that the hangers line up and the tip is centered in the bumper cutout. Adjust the position as needed. A dry fit prevents the most common mistake: overtightening before alignment.
Tighten in the correct order: Starting from the front (engine side) and working back, tighten the clamps to the specified torque (typically 35-40 ft-lb for 2.5" systems). Recheck the tip alignment after each clamp is snugged, then do a final torque on all fasteners. Torque the front clamps first, then the rear, to avoid binding the system.
Check for clearance and rattles: With the car back on the ground, start the engine and listen for any rattles or contact with the underbody. Turn the steering wheel lock-to-lock and lightly bounce the rear to simulate movement. If you hear contact, loosen the clamps and adjust the hangers. A quick road test will reveal any hidden clearance issues.

Product facts

R1-Spec Catback Exhaust - Acura Integra DE4 [2023+]: The R1-Spec single exit muffler is designed for the 1.5L Turbo Integra A-Spec (DE4) and offers a high-flow design with minimal bends. This design reduces weight and simplifies the install, but you still need to align the hangers and tip to avoid contact with the bumper.
R1-Spec Catback Exhaust - Acura Integra DE4 [2023+]