CNT / ERZ Downpipe quality concerns

Hey guys,

Heard there were some fitment and quality issues with the CNT / ERZ downpipes.

Is that still the case? has those issues been fixed?

Is the CNT catted downpipes still recommended?

I really dont want to pay the labor to tear everything apart only to find out the part dont fit correctly.

Thanks.

labor? DPs are a simple DIY. I had 0 fitment issues with my catted 5eat CNT dp. however I have heard newer ones can be finicky.

Good to hear your DP is working well for you. When did you get it?

Here's my situation in a nutshell: I have almost 80k on my car. My downpipe exhaust flange(where it connects to my greddy evo 2 catback) is rusted/rotted so there's a big leak. Stock uppipe needs to be replaced because of the cat in there. So I was planning to do Downpipe (CNT?), Uppipe (I arleady bought a STI uppipe), Gaskets (Grimmspeed?), and Tune (AP V1?) all at once. My budget is under $1000

I don't believe I will be doing the labor myself with the complexity and rustiness of the uppipe install. It would really suck if the downpipe fitment was off.

I have a CNT DP no issues with the fitment.

Thanks for your reply. How long ago did you buy the DP?

Picked it up here on the forum about a year ago, it was used but never installed.

I believe the owner never got a chance to install it and just sold it.

It can be a pain with these cars the nuts and bolts always rust out,

I'll chime in too. When I first picked up my LGT three years ago I bought a catted CNT downpipe a few months after the purchase. Drove it for about a year and a half (~15k miles) with absolutely no problems. Fitment was spot on and the exhaust smell was what it should be for an exhaust with a high flow catt in it. I sold that because I was doing sales and needed my car to be reliable while on the road so I put it back to stock. Well after a couple months, I decided I'd be fine with just a downpipe and stock catback so I bought another CNT catted downpipe and it was as good and my first. Then I was contemplating selling my car and parted everything, including my turboback exhaust, out. When I came to my senses and decided to keep the car, I bought another downpipe from CNT/ERZ. This third one had horrible fitment but I made it work. One night I heard a huge ping while going to get food. I thought it was a rock that was kicked up while driving so I didn't think anything of it. Well the next time I changed my oil, I noticed black soot at the bend under the downpipe and it was a huge crack. I contacted ERZ and their customer service was 100% what you'd want. They sent me a replacement with a return label for the cracked downpipe. The one they sent me had better fitment than the one it was replacing but no where near the fitment of my first two downpipes from them. I've had this one on for about 8,000 miles and I'm 99% sure the cat has already failed as the exhaust smell is as bad as my buddys GSX with no cat.

I believe their quality has gone down recently. I plan on replacing it with a different downpipe when I build my motor. Sorry for the long response but hope it helps!

I'll chime in too. When I first picked up my LGT three years ago I bought a catted CNT downpipe a few months after the purchase. Drove it for about a year and a half (~15k miles) with absolutely no problems. Fitment was spot on and the exhaust smell was what it should be for an exhaust with a high flow catt in it. I sold that because I was doing sales and needed my car to be reliable while on the road so I put it back to stock. Well after a couple months, I decided I'd be fine with just a downpipe and stock catback so I bought another CNT catted downpipe and it was as good and my first. Then I was contemplating selling my car and parted everything, including my turboback exhaust, out. When I came to my senses and decided to keep the car, I bought another downpipe from CNT/ERZ. This third one had horrible fitment but I made it work. One night I heard a huge ping while going to get food. I thought it was a rock that was kicked up while driving so I didn't think anything of it. Well the next time I changed my oil, I noticed black soot at the bend under the downpipe and it was a huge crack. I contacted ERZ and their customer service was 100% what you'd want. They sent me a replacement with a return label for the cracked downpipe. The one they sent me had better fitment than the one it was replacing but no where near the fitment of my first two downpipes from them. I've had this one on for about 8,000 miles and I'm 99% sure the cat has already failed as the exhaust smell is as bad as my buddys GSX with no cat.

 

I believe their quality has gone down recently. I plan on replacing it with a different downpipe when I build my motor. Sorry for the long response but hope it helps!

Wow thanks for sharing. This was the exact response I was looking for. Somebody who's been there and can tell from their experience with the old batch of CNT's vs new ones that's most likely produced by a different factory. This is a major concern for me as I'm also in sales and need reliability first. I think I will stay away from the new CNTs

I just removed one of the older CNT pipes in favor of the new GrimmSpeed. The GrimmSpeed is completely stainless, whereas the CNT is stainless except for the bellmouth. It's not a huge concern, but the bellmouth will look nasty after a season or two. The pipe has turned a straw color and has typical surface corrosion/etching after 56k miles.

The GrimmSpeed catted pipe fits great and I could use a box wrench or socket on ALL of the nuts on the turbo flange. The CNT is difficult to get one of the nuts due to the bellmouth and I have had to resort to using a crow's foot wrench.

The GrimmSpeed also has a better cat and has passed [measured] emissions in Colorado within the past year. The CNT won't do that - not ever. Unfortunately, no one has the GESI OBDII EPA legal cats on a mainstream downpipe (they are $400 retail).

I've had a CNT 3" catless bellmouth on the car since I bought it 3 years ago, and it had been on there for 3 years prior to that. It's survived some pretty terrible winter driving and way more salt than most cars see in a lifetime. Fitment is just fine and I'm not concerned with it failing at all.

Hope it helps.

When you change the up pipe, bolt the turbo to it, don't use the studs.

also replace the oil return hose. and pull the banjo filter.