[robbieracer]

After adding the SC I had P0420 and P0430 come on once in a while. I tried the sparkplug defouler method and it worked a little better but I still got the codes. I even tried welding the hole closed and drilling in a even smaller hole. It worked okay in colder weather, but once I upgraded to stage 2 SC (VT2-500) I was throwing the codes every day. Here is my attempt at making a mini cat/defouler. I cut open my old header cat and made/cut small cats to insert into the defoulers. I only threw the codes on the highway, so it may not be until next week that I can give them a good test. This was my attempt at avoiding buying o2 simulator since I don't want to cut the wires on my factory harness. Let my know what your think?

[flipm3]

Interesting setup, this is definitely my first time seeing something like this here on the boards. I'd love to hear your further experiences with the setup!

I saw in your other thread that you have 400cel cats. I thought most people shouldn't pull any codes with them. Do you have the DME recall done?

[robbieracer]

Yes, I had my DME recall done between the VT-445 to VT2-500 upgrade to see if the codes would stay away. With the added psi on the SC I think it's just blowing too much air to keep the post cat o2s happy.

[flipm3]

oh, i see. hopefully the codes clear! this would be a great solution for a lot of guys who no longer need their OE cats.

[robbieracer]

Update - The mini cats (above) helped a little, but I was still throwing codes. I decided make new ones and these have 4.5" of cat material instead of 1" (my first attempt). I have now driven 3.5 trips (approx. 180 miles) to work and still haven't thrown a SES yet, so they're working. In the past I'd always trip the SES on the first day of driving after resetting the codes. I did plug in my Autoenginuity and see a few codes for cat efficiency on bank 1, but I hasn't been enough errors to throw a code yet. I may have to rework that minicat (torpedos, as I call them) at a later time if my SES ever triggers; I made the cat material a little long and had to crush it down to get the o2 sensor screwed in and one had the cat material a little more crushed than the other, so that's probably why I'm only seeing errors on one bank and not the other.
I also built a new sect 1 with 200 cats welded at the back of sect 1 so there is plenty of room for these longer torpedos on the top side of the exhaust.
If you're N/A something like the first set I built should be enough, with a SC I needed a little more cataylst.

[M302_IMOLA]

interesting and innovative...nice work!

[Steve Jarvis]

Seems like a ton of work versus installing the electronics. It will also get more attention from the inspector than installing the electronics.

Later, Steve

[jcs4]

I had these which were the same as what you did except for i used the 400 cell ceramic version and that worked when i was supercharged (VF). I now have 200 cell cats so let me see what happens when i get the ESS kit in.

http://www.bigdaddiesgarage.com/?gcl...FQUQbAodrkoIbg

[robbieracer]

I didn't consider it work. I thought it was kinda a fun project to see if I could get it to work and have an alternative way to correcting the codes without cutting into my factory harness. I did order the 02 sim over a month ago and still haven't recieved it. I've heard of someone that mentioned it didn't work for them, so I decided to try this. So far it's working great and I haven't thrown a SES. There isn't any way to see these with the location they're in above the exhaust, you'd have to have the car on a lift to see it. But, with 200 cats I'd never pass smog, so I'll remove this and put on the sect 1 with 400 cats when smog is due.

With the VT-445 it was intermitanty with trowing efficiency codes, but I didn't have the DME reprogrammed until I installed the VT-500 kit. I think if I had the newer software with the stage 1 I would have been okay, but with stage II it's blowing more air and throwing the P0420 & P0430 codes.

[wilmar13]

So you stuffed some catalystic honeycomb in the defouler between the O2 sensor and the exhaust gas flow? I would have thought this would not have seen any flow and therefore thrown an efficiency code anyway. In a sense it is like you have the O2 sensor directly in a cat rather than behind it... or am I misunderstanding what you did?