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Hey guys - here to announce our biggest sale of the year: 10% off with code 10TAX22, which includes no taxes added (we eat the cost) and free shipping to the lower 48!

Feel free to give me a shout via PM with any questions!

 
Really considering this, I’ve been running a magnaflow dp with a 400 cell count, but was disappointed with build quality, it performs well and it hasn’t throw a code in over a year that I’ve had it, so if the cat in this unit is 400 also there’s no need for a defouler. 🤔
 
Really considering this, I’ve been running a magnaflow dp with a 400 cell count, but was disappointed with build quality, it performs well and it hasn’t throw a code in over a year that I’ve had it, so if the cat in this unit is 400 also there’s no need for a defouler. 🤔
I have also been looking into the potential need for a defouler on a 400 cell cat. Seems like a lot of people run them while others don't.

I was thinking of using one just to avoid any future headaches, but would love to know if its really necessary or not.
 
I have also been looking into the potential need for a defouler on a 400 cell cat. Seems like a lot of people run them while others don't.

I was thinking of using one just to avoid any future headaches, but would love to know if its really necessary or not.
I dropped @**** a PM, but I'm happy to address this here as well. I'd love to tell the community that a CEL doesn't pop with a 400 cell cat on every vehicle, but it's not the case (with any aftermarket downpipe, that is - not just ours). A defouler will help rectify the issue 95% of the time, though.
 
So if equipped with a defouler the rear O2 sensor will not trigger the CEL and associated DTC. The biggest issue with installing a defouler or manipulating the Bank 1 sensor 2 oxygen sensor via a resistor is not being warned of a potential catastrophic failure. I have seen this first hand locally at a buy here, pay here lot. It's a way to trick the PCM (and buyer) that everything is functioning properly when in reality the catalyst was severely impacted.

I really only suggest a defouler for non catted DP's or if the cell count is very low
Since this is a 400 cell cat, would you recommend that I wait and see if I throw a code before installing a defouler?
 
Really considering this, I’ve been running a magnaflow dp with a 400 cell count, but was disappointed with build quality, it performs well and it hasn’t throw a code in over a year that I’ve had it, so if the cat in this unit is 400 also there’s no need for a defouler. 🤔
The magnaflow is actually a really good option, it used to be cheaper and I don’t believe it’s 3”. But it does remove the restriction.

I think it’s actually 49 state legal too.

This is much better because of the 3” pipe.
 
With the CVF, the bung is angled.
On my car, it was easy to add a 45mm straight defouler with medium hole later without removing the downpipe again.

Don't need the J style with a high flow cat, only catless.
 
I haven’t had any issues with magnaflow’s 400 cell without a defouler, it’s only necessary with 200 cell or anything below 400, that’s what I have researched and my personal experience with my 02 SVT
 
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