DIY cat gut

[Sylvan Lake V35]

I have been debating down pipes for awhile now my want list is long and expensive. My G35 turned into a never ending money pit and I promised myself ypthe ///M would be kept simple. I decided to do DIY cat gut, I will follow this up with a custom tune from ECUProgram in Calgary. We will see how things go if I decide to do dynos, before, after the gutted cats and after a tune. Anyway I am not sure if anyone else has attempted this on an X5M so I thought I would document it.


My tools



About to start



The hole saw was my tool of choice



With the hole saw you can Tear up the cat material pretty quick.



The material turns to dust



On the edges there is some insulation that peels off pretty quick with the hole saw.





The issue with the hole saw is it's too short



After some pounding with a long flat head screw driver I broke through the first layer of the cat. Then there is about 1/2" of dead space and then another layer of the cat.



I pounded a hole through this layer





Just about done



Done...

[Sylvan Lake V35]

I am curious to dyno before and after to see what kind of gains if any this will give. It will certainly reduce a serious restriction.

Here is what came out.

[Gary92]

i did this once on my 1997 4runner. i thought the filter inside the cat was debris clogged up..... so basically i gutted my cat on accident

[jamze132]

How's the sound and power?

[Sylvan Lake V35]

I still don't have them on yet. Hopefully something soon.

[talon98]

pretty neat. keep us in the loop!

[Gixxerboy63]

any updates?

[TiAgX5]

How are you planning to cancel the CEL the post-cat O2 sensors will throw?

[leonelX5MRincon]

Awesome!

Thanks for sharing.... i'd like to know the difference in in-cabin-odor between a Gutted OEM Cat vs Aftermarket cat-less vs aftermarket/Custom Race cat down pipes

im looking for the one with the LEAST amount of in-cabin odor