X-Posting from G35driver for all the sedan guys.

So i purchased my FI catback about 6 months after buying my G back in 2009. since then, ive put close to 80,000 miles on it and it still sounds great. the only problem is the magnaflow midpipe that is used as the Xpipe/Resonator combo seemed to be getting more drone than it did when i first installed the system. After talking to Tony, it sounds like the packing inside the Magnaflow X was more than likely blown out, and thats what was causing the drone. Id attribute that to the HFC I had installed, as they dont retain as much heat as the stockers, and id assume the extra heat being that close to the cats was what contributed to the failure.

He reccomended i purchase a Gen 2 midpipe. the Gen 2 is what comes on all the new systems they ship, and its 100% backwards compatable. I opted for the 18" resonators to reduce drone as much as possible. its got a true X, not a muffler and it definately shows in the sound department.

Pics below.

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The new Midpipe. came very well packaged and in perfect condition. leadtime was 4 weeks on the dot.

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This is the old midsection before they took it off.

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And After.


My initial impressions on the sound difference. its WAY Throatier/bubblier. Drone is way down under cruising. it just plain sounds amazing. as far as the butt dyno goes, It feels quicker, but thats purely objective. its supposed to make more power over the original Midpipe, but not enough for any normal person to notice.

If you're itching to upgrade something, id say its worth it if you have one of the older systems like me.

 

looks good, you should upload a sound clip

 

ill take care of that in about a week once the new resonators are broken in.

 

forget it, i got impatient. heres a short one driving after about 20 miles. sounds exactly how i want it to.

 

looks nice and sounds really good too.

 

You didn't weigh each section by any chance? Wondering if there's any weight savings/gains. I will probably do this in the future. I have the gen 1 midpipe section too and it actually bottoms out a lot. Looks like the gen 2 sits higher up closer to the underside.

 

I just got the exact same upgrade done. I noticed there's a sound that wasn't there before. It happens when I let go the gas, it sounded kinda like a hissing sound. Not really a big deal but wonder if it's normal.

Found a youtube vid and he has the exact same noise (at 0:48 and 0:50)

 

^^ That would be my car in the youtube vid.

 

I was looking at a different mid pipe that doesnt have resonators or muffler but I dont have HFC. Any idea how that would change sound?

 

lol I figured it probably belong to a member here. So you know the noise I am talking about when you left your foot off the gas?

 

The hissing is the nature of the beast with this engine. Nothing to worry about.

 

I used to have the hissing sound as well on my G35 coupe, went away when I changed the FI Resonated test pipes, to MD ART pipes. Never seemed to affect anything.

 

Art pipes is the best, hands down. Wish tony lazy self could create a set for the awd.

 

I have plenty of hissing sounds with art pipes and fast intentions exhaust

 

Great sound.