OverviewThis article is written to help you install a header system on a 2007+

2.5QR motor.

Difficulty 3

Time 5.5 hours

Supplied Materials1. Stillen Header2. 5 Flange bolts3. 3 Flange Nuts

Equipment needed1. Assorted sockets and wrenches (Im sorry i will try to remember all of them, but

this install was chaos and we used a bunch of different things.2. Anti Seize Paste/Lube - i got the tube at auto zone for 4 bucks.3. FSM - EM section page 30 and 314. Penetrating oil/spray5. New Exhaust Manifold gasket (Not supplied) I went to advanced auto and they could

not get this item. Try the dealer. I reused my gasket.6. Allen Keys7. Jack stands and floor jack8. Lift or ramps9. Rubber Mallet10. Break away bar

*************************************************************************************Disclaimer: In no way shape or form do i know what im talking about. This is

my first write up and hopefully next time i will take better notes and have more time

for the installation and documentation. *************************************************************************************1. Disconnect the negative battery cable

2. Removal of engine cover and factory air inlet.



3. Removal of the top heat shield

10mm socket (save the bolts if you want to go back to stock) i threw them in the

box.

4. Disconnect O2 sensor leads.



At this point if you had an O2 puller you could unscrew the O2 sensor but this can be

taken off easily later.

5. Jack the front of the car up. If you have the Eibach and old school ramps like

me then you are screwed.

Unrecommended - we jacked the car up with a floor jack behind the right tire. As

high as the floor jack would go. We then slide the old school ramp under the front

tire and released the jack til it rested the tire on the ramp. We were then able to

put a jack stand to the left of the floor jack. Also and finally we put another old

school ramp under the rear of the passenger side tire. i was afraid to go under the

car but they assured me it was safe. yeah right!!!



6. Now that the car is jacked up, Remove the lower heat Shield.



7. SPRAY SPRAY SPRAY - Unbolting the down pipe from the rear exhaust flange.

Use the penetrating spray. The nuts/studs are tight as heck. Spray and wait a

minute or two and then try and break the bolts.



8. The Stillen directions say to remove the alternator to remove the OEM header. We

said screw it, we can work around it. Then we realized there wasn't enough room so

we loosened it, and finally took it off. We ended up striping the bolt to the header

due to not taking off the alternator.

The fix - My dad mig welded the socket to the striped bolt.



Alternator Removed





Much more room

This is the bracket for the engine cover. i suggest removing that for extra

clearance.



9. Remove all the nuts from the exhaust manifold.



As provided in the FSM - Follow the uninstall/install sequence



10. Remove exhaust manifold from engine bay. O2 sensor still attached.



11. Begin installation of the header. Use Anti Seize paste (asp) on all bolts. a. This is the step where you install the new header gasket or inspect the old

gasket and clean the surrounding area.b. Install the Stillen header to the cylinder hood. Use the two supplied flang

bolts and insert them into the two middle spots



Right next to bolts 1 and 3.

12. Cutting - i skipped this. Maybe somebody else can shine some light on this

part. Everything fit perfectly and my pops and uncle didn't want to do anything

about it. No SEL has been thrown yet, and if it doesn't throw it to often i wont

care. Since i have the bully dog gt coming shortly.

13. Attaching down pipe - On the OEM flange there are studs. Stillen has supplied

3 bolts and 3 nuts for this. Make sure to use the (asp).



14. Tighten all nuts starting with the header flange and then the down pipe.

15. Use (asp) on the primary O2 sensor. As the Stillen directions state - only get

the (asp) on the threads and not on the sensor.

16. Install the sensor into the Stillen header - the same place is at was on the OEM

header.



Since the sensor is lower on the Stillen sensor they sent wires to extend the sensor

leads. I did not do this.



Pulled the lead off of that clip there and it was able to connect to the other end.

We then used zip ties in a few places to keep the wires away from things in the

engine bay.



17. Reinstall the alternator

18. Reinstall engine cover and factory air inlet

19. Reconnect battery

20. Start the vehicle and check for leaks.

Originally posted by dldjros69