ISR Performance HGC LS Swap Header - Nissan 350Z 03-08 - 1 3/4"

The ISR Performance HGC LS Swap Headers are the dedicated exhaust manifold pair for GM LS engine swaps into the 2003-2008 Nissan 350Z (Z33). Built from 304 stainless steel with 1 3/4 inch primary tubing, designed to pair with ISR LS swap mounts and provide maximum ground clearance under the lowered Z33 chassis. The "HGC" (High Ground Clearance) designation refers to the routing, which is engineered to clear chassis components and maximize underbody clearance.

What It Does

LS-swapped 350Z builds traditionally require either custom-fabricated headers or generic universal headers that compromise on ground clearance and fitment. These purpose-built HGC headers solve that problem out of the box. They bolt to the LS engine on each side and route the exhaust path to maximize clearance under the lowered Z33 chassis, then mate to the factory 350Z Y-pipe for a clean install, or to the ISR LS swap Y-pipe (sold separately) when upgrading to a complete ISR exhaust path.

1 3/4 inch primary tubing provides excellent flow for higher horsepower applications without sacrificing low-end response on smaller-cube LS engines.

Critical Fitment Requirements

ISR Performance LS Swap Mounts (IS-350-LSMKT or IS-350-LSMKT-MO) required. The HGC headers were engineered around the engine position set by the ISR LS mount kit. Different mount brands will not produce a guaranteed bolt-on fit.

Installation Notes

• 2007-2008 build date 07/06 to 11/06: May need to modify the factory steering rack hardlines for header clearance. Check your production date and steering rack to confirm.
• LS3 engines with OEM knock sensors: Need to relocate the knock sensor to an alternate mounting boss for proper clearance from the primaries.

Exhaust Path Options

Multiple downstream options are supported:

• Use the factory 350Z Y-pipe and catback: Quick install path, headers mate directly to the OEM Y-pipe
• Upgrade to the ISR LS Swap Y-pipe and ISR catback: Complete ISR exhaust path

Fitment

• 2003-2008 Nissan 350Z (Z33) with GM LS engine swap on ISR LS swap mounts

What's in the Box

• 1x Driver side LS swap header
• 1x Passenger side LS swap header
• Gaskets and required hardware

Product Details

Brand: ISR Performance

Part Number: IS-SSHD-350LS

Type: LS Swap Exhaust Headers (Pair, HGC routing)

Vehicle Fitment: 2003-2008 Nissan 350Z (Z33)

Engine: GM LS series (LS1, LS2, LS3, LSx)

Material: 304 Stainless Steel

Primary Diameter: 1 3/4 inch

Routing: HGC (High Ground Clearance)

Required Companion Part: ISR Performance 350Z LS Swap Mount Kit (IS-350-LSMKT or IS-350-LSMKT-MO)

Downstream Compatibility: Factory 350Z Y-pipe, or ISR LS Swap Y-pipe

Production Date Note: 07/06 to 11/06 build dates may require steering rack hardline modification

LS3 Note: OEM knock sensor relocation required for primary clearance

Sold: Pair (driver and passenger)

Legality: Off-road and competition use only