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Discussion Starter #1 (Edited)
Does anybody know what's the O.D. of the header right before it connects to 786811 (OEM cat connecting pipe)

The reason I ask is that I'm planning to connect the headers to HJS 200 cell high flow cats 9095 0092:

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I'll probably use T304 SS Vibrant Performance exhaust tubing between the headers and HJS cats and for around $1100 will fabricate equivalent of Supersprint cats that run around $2500.
 

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Did you pull the trigger on the HJS cats? I'm trying to determine the real difference between the HJS cats and the $2500 SS cats. I'm actually looking specifically at HJS cats 9095 0080 btw.

Can't find any info after searching the past hour. I've read SS sources the cats from HJS so I'm beginning to wonder if it's just marketing that separates them for the $1500 difference.

What's your take per your research?
 

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Discussion Starter #3
Did you pull the trigger on the HJS cats? I'm trying to determine the real difference between the HJS cats and the $2500 SS cats. I'm actually looking specifically at HJS cats 9095 0080 btw.

Can't find any info after searching the past hour. I've read SS sources the cats from HJS so I'm beginning to wonder if it's just marketing that separates them for the $1500 difference.

What's your take per your research?
I've decided to wait for headers to arrive first. There is only one HJS cats brand and the only difference is that Supersprint makes ton of money on race cats. Sure, they spend money on R&D to determine the best proper diameter of piping to connect to cats but at the end of the day, it's very simple:

Supersprint race cats are HJS cats with mandrel bend 304SS tubing welded on each side and tubing has O2 sensor bungs welded on them.

Even Superspsrint admits it's HJS cats, not their own development. Also, people complain how HJS cats are expensive. I'll rather spend $1k and have top of the line metallic cats that will outlast $2k OEM ceramic cats. Not to mention few extra HP and no risk of CEL as long as you stick with 200 Cell instead 100 Cell.
 

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And there you have it! Ha. Thanks for weighing in. Those were my exact thoughts on the matter as well. :M5thumbs:

I'm goin' HJS and swapping them onto my 2nd set of cats. Talked to Evolve earlier in the week and the tune I recently did will prevent that CEL from surfacing as well. I feel better about saving $1500 by going HJS vs SS (aka HJS w/ T304) now. Thanks again for chiming in!
 

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...and no risk of CEL as long as you stick with 200 Cell instead 100 Cell.
Just to be clear, you will need a tune to avoid the CEL. I have evolve headers and when I got the car tuned with stock cats, I asked the guys not to mess with the secondary O2 sensors because I wanted that to serve a deterrent to spending more money on the car. I ended up getting HJS 200 cell cats and they do trigger a cel. I need to get that part of my tune re done.
 

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Discussion Starter #6
Just to be clear, you will need a tune to avoid the CEL. I have evolve headers and when I got the car tuned with stock cats, I asked the guys not to mess with the secondary O2 sensors because I wanted that to serve a deterrent to spending more money on the car. I ended up getting HJS 200 cell cats and they do trigger a cel. I need to get that part of my tune re done.
You might be right but my understanding is that HJS cats have more precious metals coating than the cheaper cats out there which matches or exceeds the OEM cats ability to catalyst the exhaust gasses.

Also, in your case you have somewhat different design headers, Evolve tune for stock cats and then you added HJS cats. I wonder if that change caused your CEL, not the actual HJS cats.

Anyway, when I'm done with my install, I'll report if CEL was triggered.
 

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Discussion Starter #7
And there you have it! Ha. Thanks for weighing in. Those were my exact thoughts on the matter as well. :M5thumbs:

I'm goin' HJS and swapping them onto my 2nd set of cats. Talked to Evolve earlier in the week and the tune I recently did will prevent that CEL from surfacing as well. I feel better about saving $1500 by going HJS vs SS (aka HJS w/ T304) now. Thanks again for chiming in!
No problem, glad to help.
 
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