If you own a Jeep with a 4.0L engine, chances are pretty good that you either have, or will have, a cracked exhaust manifold. Oft-cited causes range from bad motor mounts to poor factoryprocesses. Whatever the reason, a cracked exhaust manifold on a Jeep 4.0L engine is almost guaranteed. This was the case with our '92 Wrangler.
For the past year, we'd been driving with a cracked exhaust manifold. Other than being mildly annoying and robbing some of our power, it wasn't really a problem until it was time to get the YJ smog-checked again. Obviously, the powers that be would just turn us away with the cracked manifold, so it was high time to seek out a replacement.
A call to Quadratec put us in touch with the good folks over at Edelbrock. The folks at Edelbrock proceeded to tell us about their new Ti-Tech coated header for the Jeep 4.0L engine, which debuted in the 2005 Edelbrock catalog. The new Ti-Tech coating system is far superior to traditional ceramic style coatings, as it is stable at temperatures up to 1,600 degrees. In fact, at high temps it will actually flex, making the coating harder and more abrasion-resistant. If that's not enough, the header itself is a piece of art. The Tri-Y design header is a direct bolt-in. It uses 1.5-inch-diameter, mandrel-bent 409 stainless steel primaries, a 1/2-inch-thick laser-cut port flange, and a 1/4-inch-thick laser-cut collector flange. The header also features a limited lifetime warranty from Edelbrock and retails for $350.
As stated by Edelbrock, this is a direct bolt-in piece that went in with no trouble at all in about four hours. After finishing the install, the YJ fired right up and the Jeep sounded great. It no longer sounds like an angry lawnmower, and it feels stronger now that it is breathing properly, while passing smog with no problems whatsoever.