My flex pipe is toasted and needs to be replaced. From what it looks like to me, the rear header/y-pipe need to come off in order to weld on a new flex.

1. Is it possible to replace the flex without taking the headers off?
2. I need a 2.5" x 10" flex section. Correct?
3. Is upgrading to 3" possible/worth it it?
4. Anyone want to chime in on what they did?

 

Measure your flex section...Go to Vibrantperformance.com and look at the TurboFlex Couplings with Interlock Liners #60810 if it is a 10" unit...I would leave it installed and take it to a muffler shop and let them replace it with your new Vibrant unit...I've installed several OBX headers assys on Maxima(s) and OBX headers never seemed properly aligned nor exhibit perfect fitment so the less stress the better the fitment and life of your header assy...Good Luck! I use the TurboFlex Couplings with Interlock liner cause it's engineered for turbo usage so it actually is trouble free on Na exhaust systems....

 

Wow, thanks for the quick and straightforward answer. I really didn't want to tackle that rear header because of this. I will take your advice on the expensive flex section. I have 2 years and about 24k miles on these headers and I plan on keeping this car for more years to come. It makes me wonder how long I have until they crack. I haven't heard anyone praising these things for long life.

 

I've installed several different brands of headers on Maxima(s) and other vehicles and I never had to force a header assy to fit except for OBX...One Maxima required us to grind the cross member for clearance, another one I had to use 2 extra 3/8" flanges and 3 gaskets for the distance between the collector tube flange and the Cat flange...The Chinese have fitment problems with nearly everything I've ever built and manufacture for here! I didn't want to do it like that but the Car owners wanted headers no matter what!!! I've known of several OBX cracking in the primaries or flex coupling failing...usual after 1 year of the install...