Exhaust Headers

The Novak Conversions LSXJ3 is a meticulously engineered exhaust header set specifically designed for GM Generation III & IV Small Block Chevy V8 engine conversions within the Jeep XJ and MJ chassis. These headers aim to provide a precise fit, a common challenge in such custom applications. The headers are constructed with a robust 3/8" thick manifold flange, featuring Novak's patented port-seal surface which is face ground for gasket-less installation, simplifying the assembly process. The primary tubes are 1-1/2" in diameter, feeding into a 2-1/2" three-bolt style collector, facilitating efficient exhaust flow. Customers can choose between a natural steel finish or opt for an Aluminized Ceramic Coating for enhanced thermal and corrosion protection, which also helps lower under-hood temperatures. These headers are compatible with Gen III & IV GM V8 engines, including LS and Vortec engines manufactured from 1997 onwards (Truck Vortec series from 1999). Crucially, they will NOT fit engines with center-paired exhaust ports, which typically indicate a Gen I or II engine. While the headers will physically fit a Vortec engine with a tall truck intake, the associated intake manifold and brackets will require modification or replacement with a lower LS intake and front accessories for proper fitment in the Cherokee. Additionally, these headers are not California CARB approved. Installation in XJ/MJ chassis is specifically intended. While installers may find them adaptable to other situations, Novak recommends these headers for most known Jeep LS installations. A potential interference issue exists with the extended flange of the 4L80E transmission case when used in XJ Jeeps, suggesting a 4L60 transmission as a potentially better alternative for this application. Recommended installation for the engine manifold is high-temperature RTV sealant, though MLS gaskets have also been used successfully. Collector gaskets and bolts are not included; solid copper gaskets are recommended to prevent blowouts. The headers offer versatile routing options, allowing exhaust to pass under the oil pan, bellhousing slope, or behind the transfer case, with tailpipe exit on either side.