Stock exhaust with CHE catless downpipe

If it’s hooked up with a stock exhaust you shouldn’t have any drone. 
please follow the link to this thread where I describe what is needed. 
https://www.mr2-spyder.com/community/regular-maintenance-upkeep/che-downpipe-leaking-issues-fix/

@Dev,

So, if you had to do it over again, would you just pony up for the PPE?

If you were making a recommendation to someone who just wants to ditch their upstream cats but cannot weld and can only barely turn a wrench, would it be CHE, PPE, or suggest that they just go with a gutted OE DP? 

Time, effort, and hassle avoidance are bigger factors than cost, but lets assume that the gutted OE pipe will cost $150 plus shipping since the guy wants to keep his OE header intact... he is paranoid, just accept that as a constant parameter in the decision. He is also not excited about the $400 price for the PPE, but expects to get what he paid for, maybe even some bonus HP, so he could stomach it if he gets substantially more value by paying double. The guy has started trying to value his time. He also cannot park his car for a week or more without an exhaust while he fargs around with ill-fitting junk parts.

The more I hear about the CHE, the more it sounds like cheap junk. You mentioned good welds, but LOL, you gotta cut half of them off and weld something else on there. What a waste.

Posted by: @nottamiata

@Dev,

So, if you had to do it over again, would you just pony up for the PPE?

If you were making a recommendation to someone who just wants to ditch their upstream cats but cannot weld and can only barely turn a wrench, would it be CHE, PPE, or suggest that they just go with a gutted OE DP? 

Time, effort, and hassle avoidance are bigger factors than cost, but lets assume that the gutted OE pipe will cost $150 plus shipping since the guy wants to keep his OE header intact... he is paranoid, just accept that as a constant parameter in the decision. He is also not excited about the $400 price for the PPE, but expects to get what he paid for, maybe even some bonus HP, so he could stomach it if he gets substantially more value by paying double. The guy has started trying to value his time. He also cannot park his car for a week or more without an exhaust while he fargs around with ill-fitting junk parts.

The more I hear about the CHE, the more it sounds like cheap junk. You mentioned good welds, but LOL, you gotta cut half of them off and weld something else on there. What a waste.

All good questions and it depends.  If I had to turn back time I would go with the PPE and rid myself of the frustration of having to keep trying different things until it worked.   Now that I have solved the issue, the Che pipe can be of value to someone else once a little pipe can be welded and the use of the Rimflex gasket with high temp thread locker. This Che pipe for all of its faults can be solved so there is value.  

 As to the deeper question if I turned back time would I do it again and go though the hassle the answer is yes and that is because I learned two valuable things, the discovery of the Rimflex gasket and high temp thread locker for future use.   The Rimflex gasket has already saved a local member that needed his downpipe changed and the machining was off that it would have left him stranded. 

A long time ago I had a rounded bolt and that disaster made me buy a set of bolt outs which has saved me countless number of times over the years  along with tap and die sets and so on. Sometimes adversity brings out the best in tools and makes wrenching cars much easier and quicker. You only gain this though problem solving and a lot of google searching which is satisfying once its over. 

Posted by: @nottamiata

@Dev,

 

If you were making a recommendation to someone who just wants to ditch their upstream cats but cannot weld and can only barely turn a wrench, would it be CHE, PPE, or suggest that they just go with a gutted OE DP? 

The more I hear about the CHE, the more it sounds like cheap junk. You mentioned good welds, but LOL, you gotta cut half of them off and weld something else on there. What a waste.

 Maybe I didn't answer this question well enough. A person who wants to ditch their downpipe cat should not do so and get one that has at the very least a high flow cat.  It should be criminal to not have a catalytic converter not for the law but for your fellow man because it can be bad for people that have COPD, small kids and pets.  

As for the cats in the header its is better to get the  Che replacement header.  Its not that bad and has held up for many however I found the latest ones built very well with the provision of the ring gaskets but unfortunate it seems that the header flange leaks.  This can be solved by cutting out a Rimflex gasket, problem solved and it should give you good value and long life. 

I may have used the wrong terminology. I would not remove or disable my main cat. If I did that, I would have to forfeit my tree-hugger card.

I was speaking of the two little time-bombs in the exhaust header.

Posted by: @nottamiata

I may have used the wrong terminology. I would not remove or disable my main cat. If I did that, I would have to forfeit my tree-hugger card.

 I was speaking of the two little time-bombs in the exhaust header.

  From what I have seen last year helping a member replace a blown gasket on the Che header I would have told you to just gut your cats and reinstall the factory header because although the quality is higher with the Che there are reports of the flanges not being true because I suspect the quality to be off.  

However because I discovered a gasket (Rimflex) that will fix this problem I would recommend going with the Che header as this problem can be solved so there is no gutting.  All that is required is to purchase a blank Rimflex gasket and overlay the original gasket over the blank and cut it out using an exacto knife.  When using this gasket it is important to follow the directions and only use 20lbs of torque on the bolts and not crush the gasket and it crushes in such a way so it seals up any potential leaks. 

@dev

So, no re-welding the CHE if you just get the rimflex, and leave Popeye and the Caveman out of the install, right?

Just gotta get past the notorious Amigos, then.

Thanks, as always, Dev.

Now, if someone could kindly explain how a gasket gets blown out. My guess is that there is not much pressure in the exhaust if the tailpipe is open to the atmosphere, but I am ignorant. How much pressure is in there during normal operation?

Posted by: @nottamiata

@dev

So, no re-welding the CHE if you just get the rimflex, and leave Popeye and the Caveman out of the install, right?

Just gotta get past the notorious Amigos, then.

Thanks, as always, Dev.

Now, if someone could kindly explain how a gasket gets blown out. My guess is that there is not much pressure in the exhaust if the tailpipe is open to the atmosphere, but I am ignorant. How much pressure is in there during normal operation?

The welding was for adding a small pipe on  Che downpipe  so its resembles the same design as the stock, not the header. 

 As for the three Amigos my experience has been they are usually rusted shut  which case you have no other choice but the break them off.  

 Gaskets get blown out for many reasons but for the header they can get blown out if the material cant handle the heat and once its deteriorated it will create a gap and then leak. 

Another reason why they leak is because people think applying more torque to shut the two pieces together means a better seal but what actually happened is you now compressed the gasket to such an extent that once your car goes though a heat cycle from expansion and contraction it will form a gap and therefore a leak. 

 This doesn't mean that if you have a gasket material that doesn't work for you it won't work for a different application as some just work fine because heat may not be so high and or  the design of the fitting is better to keep tension on the parts.