[atxrhino]

I bought a set of pace setter long tube headers and im wondering if it would be easier to install them with the engine out or with the engine in but unbolted from the mounts? As it sits the engine is out because of other problems. also when hooking up the exhaust there was 2 o2 sensors on each side and pace setter has one on the header so i am wonder if im supposed to connect the cat and put it after it or what? every thing after the headers if staying stock for a few weeks till i can come up with more spare money to but the x pipe and dual exhaust.
Thanks in advance Garrett

 

[Markstang]

leaving the engine in would probably be recommended, it might be more difficult to put the motor in with the headers still on it. so unbolt the mounts and lift it a little with a floor jack and block of wood under the oil pan to give a little extra clearance.

the second set of O2 sensors only checks that the cats are working. if you leave them off, you'll just get a couple codes for that, otherwise the engine will run pretty fine. only the first sensors determine the air fuel ratio and change how the engine runs.

 

[atxrhino]

the engine is already out. cracked an oil pan so i decided to pull it. with the stock mustang why does it have 2 cat looking sections perside? and do i need them both?

 

[Markstang]

nope, the first cats are the only ones that are "checked" by the rear 02 sensor. the rear O2 sensor on my car anyway is right between the two cats.so the rear is effectively not there according to the computer.

*note* on some years the rear O2s are in the middle of the rear cat. I'd guess the computer wouldn't set off a code for catalyst under efficiency even if you got rid of the rears since the front cats would clean up at least some of the exhaust

 

[mustangmike!]

Long tubes are a pain any way you do it.

The engine needs to be lifted about 2-3'' in most cases to get the passenger side in place. Easiest to put them in from the bottom like that, otherwise place them in and then set the engine in. I actually did not try mounting them to the head, then dropping in the engine. Idk how that'll work...

As far as O2 sensors, your fronts will go into the LTs, and your mid pipe should have bungs for the rear sensors. Possibly that is, if not, you'll need some welded in. Or since your running long tubes, why dont you just have the rear O2 sensors turned off

 

[robb15033]

http://www.supersixmotorsports.com/pdf/LongTubeInstal.pdf
-I hope this helps everybody/anybody. It is detailed and honest about situations where there is clearance issues and other very important area's of the headers location relative to possible rubs, vibrations on start-up.