ND Header Factory Manual Install.
1. Remove shock tower brace if you have one installed.
2. Relax the cooling line that runs above header area by removing bolt that holds it toward passenger side fender, and loosen the other bolt that holds it near front cross member. Stock header can then be unbolted per diagram above and lifted straight up.
LONGTUBE HEADER TIPS
INSTALLATION NOTES: Given the big size of the resonator we suggest those actually racing give extra support by swapping the factory rubber hanger for the midpipe with one of the thickest rubber hangers from the rear. Two people doing the install makes it much easier, having a lift makes it much easier, thus professional install suggested.
Start with removal of shock tower brace, disconnect passenger side motor mount, disconnect two bolts holding coolant lines to chassis above header (no need to drain coolant).
Remove factory header and studs holding the header to motor.
To install the longtube you will likely find it much easier if you jack up the motor to give yourself more clearance on the passenger side of the motor. Before jacking up the motor start the process of the longtube going into the car, one person from above can lower header to one person below the car. Once it is down as far it will go you will likely find you need to jack up the motor for it to drop the rest of the way into position. Same torque specs as factory header per factory service manual page above. Currently fitment is MANUAL TRANS and LHD only, no promise is made of ever fitting RHD or automatic but if we get the chance to check fitment we will update this sentence accordingly.
With some force you will discover that you can change the angle of the flex joint in the midpipe, once your muffler of choice is bolted up make sure you have at least half inch clearance between muffler tip and plastic bumper cutout, and as needed you can yank down on the exhaust tip as your other arm pushes up on midpipe exit flange and you will feel the flex joint change angles until you get the necessary clearance.
Note we have found there is risk with our RACE muffler of melting bumper cut-out if not careful, only our Race muffler has tip that is not rolled, which means it gets really hot. All our other mufflers with rolled tips do not share that risk. You will find the setup takes both factory O2 sensors, one up front just like factory setup and second sensor after converter just like in factory setup (the only difference is sensors are moving downstream a little because first converter is downstream).