The kit:
Boosted Performance twin scroll with a PTE 6265 BB T4 turbo, 452whp and 420ft/tq.


Issue:
Smell in cabin when windows are down, when A/C or heat are on... smelling clothes..ect. Was getting tired of smelling like exhaust fumes if I go out…sound like a bee? Maybe, but I don’t care.

Solution:
Mil-spec 100 cell catalytic converters

I wasn’t sure what route to take with this issue. Read a lot about people dealing with the same problem, and decided to call Eric at Mil-Spec. He was very helpful, and advised me to try the 100 cell metallic converters:

http://www.mil-spec.org/3.0-100-Cell-Weld-In-Cat.html

So, I had a bit of time this weekend, and decided to tackle this project:










Rather straight forward, but time consuming. The cuts need to be perfect because I was only working with about 16” of total linear space.


Results:

The two 3” converters did a wonderful job. The smell is completely
gone, even right at start-up before everything warms up. The
exhaust tone did not change at all (surprisingly), and the butt dyno
shows no indication of power loss. Overall I am very happy with the
results, and even more impressed that the car did not feel any
slower, or less responsive. Dyno results/comparison of before and
after would be ideal, but not an option at this time. I would suspect
that at higher boost levels and power, there would be a bit of a
difference, but for me, right now…this is perfect.


Hope this helps others when it comes to this sort of an issue.

Sasha

 

This is awesome! I have a similar issue and don't really know where to put the cat.

Glad to see somebody taking the initiative and doing some R&D here.

I was going to weld in a single 3" 100 cell cat in a very similar spot but two seems like a better idea!

 

Interesting...so why dual cell/pipe instead of single straight cell? More flow?

 

I made it with two of them to keep the flow as high as possible. I think that this is why there are no noticeable performance loses.

 

I've been running two parallel 100CELs on my MTM setup for a few years now.

On a G I have them placed a bit further back (behind the cross-member) and then branch (just one Y) out to two Magnaflow 2.5" resonators + mufflers.
I've noticed minimal power loss at up to the 540rwhp level.. They do a reasonable job of taking the edge off the stink. So mine works well , but not nearly as purdy as your new setup...