Constantly failing gasket on Cobra Y pipe

[skate2create]

Afternoon all.

 

I've got an issue whereby my cobra Y pipe seems to eat through gaskets on the driver side branch.  This will be the third time I've replaced gasket(s) now in only a few thousand miles.  I thought it may be due to unflat mating flange on the factory CAT section, however it was cleaned up the last time it was changed and a flat edge placed against it to check if it was warped (it wasn't).

 

Initially I ran with one cobra supplied gasket on that side when the Y pipe was first install, which blew out from the bottom pretty quickly.  I then switched to a sandwich of 2 cobra supplied gaskets after cleaning up the mating flanges to see if that would hold a good seal and it's gone yet again in the same place.

 

I'm stumped.  My local garage who deals with classic cars has suggested there may be manufacturing intollerance somewhere along the line and also in their experience it's not uncommon for exhausts on classic cars (is a Z deemed a classic now?!) to be so out of wack that you end up having to use upteen gaskets to make it hold a seal.

I don't doubt his knowledge on the subject, but that doesn't answer help me!  Has anyone else had this issue and have anything to suggest/ try before I waste more time changing these sodding gaskets again?!

TIA.

[nissanman312]

@Sim found some that seem to last I'm sure hell share his thoughts 

[skate2create]

I tell a lie, I still have the cobra supplied gaskets from last time as they didn't look like anything special/ were the same as the first ones that blew out.  These are the sort I fitted last time with ultimately the same issue:

 

350Z gaskets

[Umster]

Hey, I had the same issue with my 370z cobra exhaust. Glad you checked the flanges because they're usually the culprits. They usually don't sit well and need smoothing down. 

 

I'd recommend getting stock Nissan gaskets as they're usually the best. Aftermarket gaskets tend to be terrible for whatever reason. If you bought direct from Cobra complain to them and they'll send you replacement gaskets FOC if you don't wanna buy stock. Though again, I wouldn't recommend them and have been told they aren't the most fit for purpose. 

 

The tolerance issue is genuine with Cobra. You get what you pay for unfortunately. I've been told by fitters how they always have one issue or another fitting Cobra systems. 

[skate2create]

I mentioned it to @MITZ@CougarStore when it went it blew out the last time and he kindly got in touch with Cobra who sent me 2 replacement gaskets.  They didn't look particularly special and my garage said the same, so I went with a couple of the ones above as they had the fire ring on the inside.. not that it made much difference clearly!

I'll seek out some OEM spec gaskets, I think Torqen sell them, and see how I get on.  If this blows again I'll have to get a different Y pipe I guess!

Edited May 29, 2019 by skate2create

[Sim]

On 29/05/2019 at 12:52, nissanman312 said:

@Sim found some that seem to last I'm sure hell share his thoughts 

@skate2create I got some made up, I run FI and was burning gaskets out way too quickly, I used REMflex ones for one side of the CAT, two bolt CAT to Y, and got the header to cat (the warmer side) 3 bolt sort of triangle shape made up by a gasket manufacturer, RAM, these are similar to the REMflex ones, both the RAM gaskets ones and the REMflex ones are thicker and can take up the irregularity caused by slightly warped flanges. I haven't had any problems since flipping over to these.

 

I believe that @Adrian@TORQEN is getting the 3 bolt ones made up by REMflex as well but I'm not sure.

 

If you cant find RAM, message me and I'll dig out the gasket company details as they were very helpful

[skate2create]

Hey @Sim, Cheers for the reply.

It's the 2 bolt gasket from the back of the OEM Cat to the driver side branch of the Cobra Y pipe that keeps blowing out of the bottom, even with clean/flat mating faces and 2 gaskets used.
I think I've found RAM on ebay (and in turn their website) and have found Remflex too.  Do you remember a ball park figure on cost for those gaskets at all before I go enquiring, just so I know what sort of quotes to expect before I take the plunge.

TIA  

[Sim]

On 05/06/2019 at 10:13, skate2create said:

Hey @Sim, Cheers for the reply.

It's the 2 bolt gasket from the back of the OEM Cat to the driver side branch of the Cobra Y pipe that keeps blowing out of the bottom, even with clean/flat mating faces and 2 gaskets used.
I think I've found RAM on ebay (and in turn their website) and have found Remflex too.  Do you remember a ball park figure on cost for those gaskets at all before I go enquiring, just so I know what sort of quotes to expect before I take the plunge.

TIA  

Sorry for late reply been working away.

They were about the same cost as the Remflex but I had to.send patterns. So it's the 2 bolt round/oval one, it would be cheaper for you to buy the Remflex one.