I'm currently in the process of replacing my exhaust manifold with an APN header. I decided to go ahead and order a new front pipe,2.25" Walker (the one that connects from the header to the catalytic converter). But like always a problem has arisen: The goddamn connection to the cat is not coming off. the bolts (or studs?) and nuts are seized on tight, and everything is just rounding the nuts.

So I'm making this post asking for suggestions on what to do from here. I'm not in a rush, since I'm just going to put the header on and use the current pipe.

I'm stuck between sawzalling the whole connection ordeal and welding a pipe there to connect the cat (which is an aftermarket spun highflow) and the front pipe. But, this would cause more exhaust vibrations I'd assume.

OR

Using mental magic to figure out a way to cut the current pipes apart, but spare the cat side from destruction.


ANY help with figuring out either way, or a better way would be EXCELLENT.

 

Not sure what your asking but if your refering to the factory clamp to hold the cat on theyre so damn tight youll never slide it off cut the pipe right before the clamp and weld on what you have to to make it work

 

NVM i see what your asking i would drop the cross member and cut the bolts

 

Yeh, I was pretty tired when I was typing that ha. I'm not going to bother with it today. Rather just get the header on and get my jeep road bound.
Thanks

 

I got to ask why 2.25 downpipe? If your doing the work your putting a restrictive crush bent 2.25" pipe in its going to be holding back all the other work you did on the exhaust.

 

cutt old down pipe infront of cat flange remove exhaust to muffler shop let them heat it up and remove bolts them put ib back on new flange

 

Either cut the bolts off with a cut off wheel or a nut breaker and then hammer the stud out

 

Honestly, I got a 2.25" stock style pipe to avoid going to an exhaust shop. While that plan is seemingly falling through. The company that makes the pipe however did not make the crushed part,to clear the drive shaft during articulation, like the true stock one has. So it will be a slight upgrade, if that. If anything it's to not have a stretch of pipe fouled by an oil leak ages old.

My plan was to have stock sized piping down to the cat. Then after the cat expand to 2.5" to the muffler and tail pipe. I already bought the highflow cat and installed it, so backing down on that seems silly. I'm also not aiming to be but so loud, regardless of the whole idea of "sound=power".


thanks FreeGdr, I'll write it down for possible things to discuss when I head to an exhaust shop. Some of the places around here are a bit eh.

 

Are you sure that pipe isn't crushed like stock pipe ?

Looks like it from the 1 pic.

Do you have or can you take another pic of that area ?

Looking to get this pipe without the crush.

Very much appreciated.

 

I also have a walker down pipe in my rig. There is no axle clearance "crush". However I was very displeased on the fitment of the pipe. The o2 sensor placement is too close to the oil pan and the pipe prevents the removal of one of the inspection cover bolts.

 

Walker down pipe is complete trash. Save your money and buy from the dealer. I've got the walker mini cat down pipe on my. First there was completely shoddy workmanship, they never trimmed the pipes where they met, and then after my mechanic finally got it on and in place, the front pipe is off by about and inch. Due to that the pipe constantly bangs into the drive shaft, and when the axle articulates it has attempted to take a bite out of the pipe. For how much I spent I expected better.

 

Well this is good to know before I actually went ahead and did some cutting.
Not really info I wanted to hear though. :/

Guess I could always just go up to an Exhaust shop and have them custom make something worth a damn.

 

I never had any issues with the APN and walker pipe, one thing tho is the walker pipe doesnt have the clearance dent so i ruined my pinion bearing and header by jumping the jeep with stock bump-stops. Manly my fault for not bumpstopping the front after my lift but you learn.

Going bigger with the exhaust isnt always better, too big of exhaust will hurt torque and HP.

 

I honestly don't plan to get 2.5" pipe for my frontpipe. But with your success with the pipe, I'm at a coin toss between using it and just trying for a custom mandrel bent 2.25".

Also, ouch.