yes...slight on my mid pipe and i have torn up the braided stainless on my y-pipe...but its not all the way through

at some point, i am going to have these pieces replaced while the exhaust is on the car. i am hoping that the welder can relieve some of that binding with the exhaust

 

I also tore the braiding on my Y pipe but that happened before I got Cats. I did crack one myself by scraping it on a speed bump but I paid for that one, its the other several replacements when there was no bottoming out or scrapes of any kind that concern me. Also cracked with stock headers and later with DC Sports headers. I hope to have better luck with test pipes so far nobody has chimed in with a cracked test pipe so I will consider that to be good news.

 

if you're cracking heads, twice, then something's either wrong with your car or your driving abilities.

 

i guess my test pipe, y pipe and mid pipe were all cracked due to the damn nismo exhuast...

 

sounds like bad combination set up. change one of the mods and see if the cracking persists.

 

Read the thread I linked below...

andy@performance also has the same setup as you
and seems like he figured out a way to solve the problem
with some spacers and lowering the M-bracket.
He also posted about it within that thread.

https://my350z.com/forum/showthread....c+y-pipe+nismo

 

The heads arent cracking, its the welds on the Crawford HF Cats and it has nothing to do with my driving as the current pair cracked during breakin of my new engine and tranny and with less than 500 miles on it I have been driving like a grandma to break it in properly.

 

This was done on the first install of the cats back in Nov 05.

 

Damn and it still cracks?
I guess no Crawfords for me..

 

i am also lowered and this creates another problem because the exhaust hangs down lower than i would like. the only way to improve this would be to modify the exhaust and/or hangers so that the exhaust sits up higher and also relieve the binding.

i don't know what version crawford cats i have but i am very happy with them as far as performance goes. fitment was also perfect when i installed the exhaust so i am not sure what causes the cracking on the welds of the cats.

i have dc headers, crawford cats, fuji y pipe and ti catback. i am really happy with this setup and will make repairs or mods as needed. not sure if the problem is specific to my particular brands and their fitment. i see the cracks as a minor problem and i am just careful when driving around not to scrape on anything.

 

oh, my bad, i missed you cracked it WITH...I thought you wrote you cracked both headers, hehehe. My bad

 

Kinetix High Flow Catalytic Converters. 7,000 miles and looking good (knock on wood).

 

Thanks to all the threads about crawford cracking, I decided to go with the Kinetix cats as well. Order has been placed!

Also, could not find sufficient data to show that crawford performed better for the additional cost.

 

You'll like the Kinetix, they are darn nice for the $. Make sure to bend the heat shields above them up a little, if you don't they tend to rattle on the cat and make an annoying sound.

Thanks,
Gary

 

I think I earlier said the crack was near the headers, its actually the weld on the Y pipe side of the cat and its always the passenger side cat that cracks. The weld is also very thin and tall which I believe to be the ultimate reason for cracking. Either way, they are now history and have been replaced with UT-R Resonated Test Pipes(Nice quality welds). WOW MY CAR IS LOUD. Never thought I would say this but from 2k-4k rpm it maybe almost too loud. I am getting used to it though and because I am breaking in a new engine and tranny I have been granny shifting. I like to run her around 3500-4000 rpm normally and it isnt as raspy and loud after 4k rpm so I figure once shes broken in the loudness wont be much of an issue but I will have to stay off the throttle when the poligs are around. Feels great sounds great all around, there is Rasp but it doesnt sound ultra crappy like I have heard on some other rides(not Zs though). Deinitely not for the meek or concervative types though. Very Very Agressive sounding, car pulls easier too but again I wont be able to give it a real butt dyno run till after 1500 miles so I got another 1000 miles to go.

 

*fart* *fart* *fart* *fart* *fart* *fart* *fart* *fart* *fart*

 

I had the oem brace on and modded the Helix cats to use it. That equaled cracked cats in about 3 months. Ditched the brace and went to Kinetix cats. We'll see.

 

I've cracked two sets of non resonated test pipes, my drivers side resonated t-pros test pipe twice at the header flange and a t-pros y-pipe at the collector so far. Don't buy ebay crap like I did. In all instances I needes something cheap and fast and that's the reason I bought that crap. No more megan/tpros/china crap for me!!

 

Looks like a true dual exhaust. Any aftermarket cats or test pipes have a less chance of cracking due to less stress and flex.

As of right now, Crawford is not selling the cats because they are doing R&D on them. I have to admit that the Crawford cats are a perfect compliment in all aspects for the NISMO exhaust excluding the fact of the problems with cracking. I am working with Doug to find a solution, so far my cats have lasted and I currently have the new prototype on them, exactly the same, just different welds. Hopefully we will have this issue resolved and will be available for sale again. It would be ashame to discontinue these cats because they are a great mod and make any cat back exhaust sound and feel a lot better. I'll keep you guys updated. FYI, the only cracked cats weve seen are ones that are installed with the NISMO exhaust, we have had them installed on quite a few different setups, I.E; HKS, Stillen, GReddy,etc. It seems like exhausts that are true dual or use H pipes have no problems what so ever. If you have the NISMO exhaust, you can probably even change out to a different y pipe like the JIC or Tanabe and can avoid the cracking problems.

 

Just wondering...

When using a JIC y-pipe on the NISMO exhaust + crawfordz cats, do you still need to put washers on the M brace? Thanks