I don't see why you can't do it yourself, just put your car up on jack stands, granted itll be a pretty tight squeeze but I'm sure you can do it. I've done my exhaust setup numerous times without issue but then again that was with the cb and the rtp's.
Let us know how it pans out.

 

Yea ill check the heatshield tomorrow, but what about the second issue? I did a rev up to 5k today and still its quiet as anything as soon as i let go of the gas pedal. Dont hear any infiniti resemblance as the exhaust is depressing/winding down. Help anyone?

 

^^^

 

yeah check your exhaust manifold. things get loose then they rattle, usually arent a big deal

 

Its most likely the heat shield. I had the same problem after installing my magnaflow because there isnt much clearance. It was always on startup and for about the first 15-20min of driving in cooler weather. Once the pipe expanded all the way and was all the way up against the heat shield it would stop. I bought some cheap radiator hose and stuck it in-between the pipe and shield and it took care of it.

 

Not sure if what im calling a heat shield is a heat shield lol but its the only thing the exhaust actually goes up and over after the Y pipe on the midpipe. Its like a brace or something.

 

my G makes the exact same rattle during cold startup. humming vibration.
in for answer!

 

I'd say heat shield, maybe an exhaust leak?

I somehow feel your issues of no "gurgle" as the RPM's drop is connected to the metallic noise you are hearing.

 

mine used to do the same thing... My guess was the heat shield...funny thing is...it only happened when it was really cold out...ever since it got little warmer around here i never heard that noise again. But yea as for the second part...mine also used to do that when i first got the car...no distinct infiniti exhaust note but that problem also went away on its own...i think my car just fixes itself somehow

 

Hahaha funny that you say that, that infiniti note when the rpm's drop actually went away ever since it got way warmer. Now the other part still exists but i'm pretty sure its just the heat shield which should be an easy diy fix. Now will it do any harm if i completely remove the exhaust/cat heat shield? i've heard that some people just took it off without a problem but i'd like to confirm that before i go through with it.

 

well buddy of mine removed his heat shield cuz it was rusted to all hell on his fx35. it doesnt seem like its giving him any problems the last 4 years but who knows...

 

Yea i just dont want to start regretting things on my G after i take them out.