maximatech12

Tried installing Magnaflow 51732
What a pain in the neck!
The outlet pipe didn't even fit with the Nissan tube assmbly sleeve.
I wound up giving up after stripping half the threads in two of the pin bolt holes.

It claims OEM direct fit.
The outlet tube is the same size as the
sleeve.

maximatech12

Would hollowing out the cast iron Cat effect the core charge?

sanford7575

Hollowing out the cat should not effect the core charge. The Exhaust Manifolds are one of the biggest pain points on the Maxima / I35 in my opinion. When changing out my entire exhaust last year, I broke 4 bolts on the front and rear manifolds while replacing the pre-cats and I had to drill out the broken bolts which was a total PITA! On the bright side, after doing the job, I am intimately familiar with my Maxima and now have no fear about fixing anything else that may go wrong!

maximatech12

The 3 Bolts that attach the front cat to the y-pipe are 10 X 1.25 size bolts as are the EM studs. 10 Is the diameter and 1.25 Is the thread pitch.
If you peeled the heads off of the cat bolts try drilling a hole into it. The heat and friction from the drill bit should break it loose and get it spinning.

maximatech12

Also the catalytic converter has woven strands of metal inside of it which may be platinum. This may be why the core is $140.
So if you want to eventually bring it back to stock you may wanna hold on to that.

Derrick2k2SE

iTrader: (3)

It's going to take a lot more than that to extract a broken exhaust bolt. Even using a left handed drill bit wont get it moving. If you think you're going to generate anywhere near the heat you're talking about you're going to destroy the bit within seconds.

maximatech12

after reinstall of this manifold with the thread repair I was concerned the studs would mangle the thread repair.
the stud would normally stop at the hole where the threads separate.
I was horrified that this would happen so I backed off the torque and let it go.
needlss to say, I began seeing black carbon building up on the valve cover.
also recently I noticed a carbon smell after putting the air on..
the blower motor was sucking up the exhaust coming out..
I wound up replacing the studs with bolts.

could a manifold leak cause performance issues as well?
...notice since tightening these bolts down the car runs better.