Borla and Mike Leach headers have been discontinued.

Doug Thorley headers are now only available for '00-'06 4.0L Jeep models with dual precats (part no. HDX-635)

Edelbrock have produced a new shorty header that fits '91-'99 4.0L Jeep models (part no. EDL-65923). Edelbrock shorty headers feature mandrel-bent tubes, laser-cut or die-stamped flanges, and a black painted or glossy nickel/chrome plated finish for great looks. They're direct replacements for the stock manifolds, and they're easy to install using the factory crossover pipe. Best of all, Edelbrock shorty headers are 50-state legal under CARB E.O. #D-215-45.

Gibson Performance Exhaust also produce shorty smog-legal, heavy duty headers with the options of chrome plating, stainless steel, or ceramic-coated stainless steel.
Mandrel Bent Tubing
Heavy Duty 3/8 in. Thick Laser Cut Port Flanges
Premium Gaskets and Hardware
No Welding Required
Uses OEM Style Connections

Clifford Performance 57-2015 "6=8 HEADERS" Jeep Headers 1987-2005 w/ 242 cid (4.0L).
Fitment: All 1987-2005 Jeeps 242 cid (4.0L). Includes smog fittings. Description: This is a shorty street rod header which includes the header gasket and street hookup kit. Average gains on a stock engine are 18-22% when bolting on this header. By seperating the heat created by the engine in to two collectors, we can increase the life of the engine and make more power with exhaust scavenging. Want to use a single exhaust? Use our universal -Y- Pipe (09-0240) to single out the exhaust to bolt to your stock exhaust system.

Banks Torque Tube Exhaust Manifold Assembly.
4.0L 6-CYL: 1991-06 WRANGLER, 1991-01 CHEROKEE, '93-01 GRAND CHEROKEE, 1991-92 COMANCHE: Banks TorqueTube is a streamlined exhaust manifold designed to optimize exhaust flow and engine efficiency. Because the stock manifold's flange does not align squarely with the ports, flow is restricted. TorqueTube corrects the problem with a half-inch flange that is machined dead flat, and precisely fitted to the port pattern. You can hear the difference in the plusher, healthier exhaust note.
Unlike the stock, failure-prone exhaust manifold, Banks TorqueTube is built of heavy, 409 stainless steel to weather a lifetime of heat, stress and abuse. The flange, welded to the tube assembly on both sides, will never crack or separate. The gasket is made of SMI 900, a material that stands up to super-hot temperatures.
Bolts right on!
Stainless, constant-diameter head-pipe assembly available for the best flow ('91-95 Wrangler only).
Includes: Stainless TorqueTube exhaust manifold assembly with mandrel-bent primary tubes, seamless Y-collectors and flange; Gasket; Mounting hardware.