Exhaust Manifold Question.....

What is the difference between these and how do they compare to the APN and other possible headers?

#J960708​

± Click view full size image Part NameJeep Cherokee Exhaust Manifold (J960708) Year1992 Engine - Chassis4.0L, 6 Cylinder - Cherokee
DescriptionEXHAUST MANIFOLD -- Exhaust Manifold. 6 Cyl, 242 CID (4.0L), Laredo, Briarwood, Sport, Laredo, Postal, Country, SE, Classic Model, Tubular Design, HOL#327-1533, Ground Shipping Only. BrandReplacement Your Price$123.99

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Replacement Exhaust Manifold
1991-1999 Jeep Cherokee

"EXHAUST MANIFOLD -- A High Quality, Direct Fit OE Replacement For Exhaust Manifold"


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I feel pretty confident in saying those are different pictures of the same header, one with the gasket attached to the header and the other without.
In any case, the headers pictured don't seem to be very high peformance. Look up the exhaust article at www.go.jeep-xj.info for starters. The gist of it is that you want all the exhaust tubes to be as long as possible - the headers pictured just aren't optimized for torque.

those are pretty much stock replacements.

Fine if you are running a cat and any real muffler. No real HP gain with them, maybe a little. Mostly for replacement. They will not heat the engine compartment up as much as long tubes will. May not get in the way like long tubes can with custom suspension. A fine set of pipes for most offer (IMO).
If you are running open headers then go for the long tubes else long tubes are good for little more then bragging rights.

only 2 pipes going to the collector not six. Looks like a good stock replacement, maybe a few more ponys out of them, especially if your current manifold is leaking. However they are not a header.

Near as I was able to tell, all of those aftermarket bellows style manifolds are MIC (made in china), and do a decent job.

The same part from the dealer is $500.

I noticed a bit more engine response, and nicer sound from an APN, but nothing amazing.
The flange is thick and was very flat, thats a very nice feature in a header. I've had no vaccum leaks at all.

Compared to an APN manifold, the accordion style manifolds are a bit easier to install, because the two bolts in the rear are more accessible.

The APN obstructs one bolt so well, it has to be tightened by a box wrench or crow's foot