ISR Performance Short Tube Headers | VQ35DE | 2003-2006 G35 & 2003-2006 350Z | T304 Stainless | Equal Length Primaries | Boost Power & Sound | Direct Fit OEM Replacement

Unlock hidden power and sound from your 2003-2006 Infiniti G35 or 2003-2006 Nissan 350Z VQ35DE with ISR Performance Short Tube Headers designed to replace the heavy, restrictive cast-iron factory exhaust manifolds that choke flow and trap heat, because the ISR headers use equal-length 1.625" mandrel-bent T304 stainless steel primaries that feed into high-flow 2.5" collectors with a smooth merge design to improve exhaust velocity and cylinder scavenging over the crimped OEM manifolds, freeing up 8-12whp and 10-14wtq with a tune while adding sharper throttle response and stronger mid-range torque that pulls harder from 3500 RPM without sacrificing low-end drivability, and the sound transforms from quiet and restricted to a deeper, aggressive, exotic VQ tone with louder cold start, cleaner mid-range, and a refined high-RPM scream that gives you real header tone without the rasp or drone you get from test pipes alone, and the entire header is fabricated from heavy-gauge T304 stainless with full-penetration TIG welds, 3/8" thick CNC-machined head flanges that won’t warp or leak, and direct-fit 2.5" outlets that bolt to your factory cats or aftermarket test pipes with zero cutting or welding, and the short tube design keeps primary O2 sensor placement in the factory location for easy tuning and emissions compatibility while tucking tight to the block for perfect ground clearance on lowered cars, and fitment is 100% direct bolt-on for VQ35DE RWD using all OEM mounting points, clearing the steering shaft, motor mounts, and subframe on manual and automatic cars with no rattling or interference, and the kit includes multi-layer steel exhaust gaskets and Grade 10.9 hardware for a leak-free install that survives daily driving, spirited canyon runs, and track days, and they pair perfectly with ISR test pipes, y-pipes, and cat-backs to build a full exhaust that maximizes NA VQ35DE power, so if your DE G35 or 350Z feels restricted, sounds quiet, and you want proven bolt-on power and tone without deleting cats or fighting long tube fitment issues, ISR Performance Short Tube Headers are the strongest upgrade to kill restriction and unlock sound and response, and every set is jig-welded, pressure-tested, and QC inspected for flange flatness, primary alignment, and weld penetration so you get ISR’s legendary flow, fitment, and tone without the cracking, leaks, or warping you get from cheap eBay headers.