Reviewed by Ken P (Myton, UT) Reviewed for a 1993 Jeep Cherokee — 2010-11-12 08:35:41
These headers have added to the power and ease for pulling hills and acceleration. Still checking mileage, on my 4.0L 6cyl. engine so far appears to have improved (was getting 17-18mpg, now looks like 20mpg) I'll a better idea after my next fill-up.
Installation required a little bit of modification to the wider bases between the first and second and the fifth and sixth exhaust ports. The intake manifold for my fuel injection system would not fit between the slightly wider base flange (than the original manifold) metal. I ground away from the inside of each of those ports, approximately 3/32", which was a minor inconvience extending the installation time by about 45 minutes. Knowing in advance will reduce that time significantly.