Stock CATS? The SC's will burn out over time much faster the HFC's or TP's. I'm suprised by the recommendation to go with Stock cats especially when forced inducted.

 

All I know is my car runs way better with Stock cats and I made more power with them. My HFC's didn't last long either so not sure why stocks are better but I went with Stillen's recommendation and glad I did.

 

Interesting......

After a while though the stock cats cells are going to deteriorate expeditiously due to the increase heat.

 

Hopefully not as fast as the HFC's did. I am sure over time they may go bad. With forced induction I just feel the car runs much better with the stock cats. Naturally Aspirated I would have kept the HFC's on though. With the Stillen SC the HFC's I was running only lasted 600 miles.

 

Alvin in toronto also made great power on stock cats then switched over to HFC's and made less power which was interesting to me. I think he mentioned he was going back to the stock cats as well.

 

The construction/material of the stock cats is more resilient and resistant to heat. As Diego said, they will eventually wear out. However, we have seen stock cats last past 100k miles with our supercharger kits. They will go bad before they blow out which will throw a CEL letting you know they need to be replaced. If you want more info let me know. The details of materials and durability get boring and technical.

 

I had stock CATs in and they blew to bits... Then aftermarket exhaust with TP and blew the resonators apart.

Then new aftermarket exhaust and blew the resonators again, and mid muffler. Sigh...

Finally with another aftermarket exhaust I have performance resonators again and everything else is straight piped. The resonators still blew... I gave up. I have blown resonators and keeping it that way

 

Going back to stock cats. Not only more power but a better torque curve as well.

 

All depends on the tune

 

Stocks cats making more power than TP's is questionable and for how long would SC's hold up when compared to test pipes? I recalled when I was supercharged with the Stillen Kit back on my old G35x with the V3-trim and I ran with the stock cats those things disintegrated so fast it was unreal.

 

The tune has very little to do with it. The power loss comes from lower boost in the cylinder. The stock cats provide enough back pressure to keep most of the pressure in the cylinder that is lost in some of the timing overlap. Yes you can save some of that with tuning but there isn't enough range in valve timing on the stock cams (not that there are aftermarket options) to get it all back. We've seen countless people experience the power loss with test pipes and HFC's. It is simply how the supercharger system on these cars works.

It's interesting that this is the first time we have heard of the stock cats blowing out and disintegrating with the supercharger.

 

Perhaps because not to many folks are using Stock Cats but instead TP's and HFC's. So as we're engaged in a discussion as such. We're hearing more incidents of stock cats failing, and not holding up well while under Forced Induction.

 

So far I have 900 miles on the stock cats, I will keep everyone posted on how long they last. My previous HFC's only lasted 600 miles maybe less until I noticed they were bad. So far the stock cats are great. No signs of any issues.

 

We have done extensive testing and research on this subject as it baffled us as well. We also spoke with various catalytic converter manufacturers who use various materials in different types of catalytic converters and after all was said and done...we're talking years of testing and research here...the end result was that the stock cats hold up better than any aftermarket high flow cat currently available.

The general consensus is that the factory catalytic converters use two large bricks where as high flow cats use a smaller single core. This means that all of the heat coming out of the engine/exhaust is going through a very small core in comparison. The HFC simply can not withstand this increased demand and begins to break down prematurely.

During our research and testing we have worked on everything from 2.5 liter N/A 4 cylinders to 5.7+ liter supercharged V8's producing close to 700HP.

We have also discussed this in great length with all of the top catalytic converter manufacturers and even CARB test labs who test these cats for EPA and CARB emissions certification.

I am currently working with and testing a new product that probably won't be ready for release for another year or more. We are in the very early stages of development.

 

Would test pipes with a slightly smaller exhaust give the necessary back pressure?