I am pulling a 5.0 from a '98 Mountaineer and dropping it along with the 4R70W into the Bronco. I had assumed that I would simply keep the EGR system since it was running fine. Now that I got far enough into tearing it down I found out that the EGR tube ties to the passenger exhaust manifold and since I really would like to go back in with headers that will be a problem. I'm sure I could find a way to plumb the EGR tube to somewhere in the headers but it would almost certainly be upstream of the collector so it would be on a single cylinder. What is the downside of simply deleting the EGR valve/tubing? I'm also assuming that when I get the ECU up to EFI Guy that he can make the computer "happy" with no EGR. I haven't looked closely at it yet but I should be able to pull the EGR valve and make a quick cover, in on and be back in business unless there's something else I'm missing.

The downside is you lose a tiny bit of mpg at cruise (if you're the kind of guy that can keep your foot out of the pedal). You can remove the big EGR elbow altogether and bolt the MAF directly to the throttle body, no need to make a block off plate. I can make the computer happy (for OFFROAD vehicles anyway).

So how restrictive are the stock manifolds? Am I better off just keeping them and not worrying about headers?