Removed my secondary cats.

Ducklakeview · Post by **Ducklakeview** » Thu Mar 30, 2017 1:43 pm

Ok, so rather than replace with straight pipe, I whipped them off and removed the heat shields before cutting a large hole in the top of the cat with the plasma and removing all of the insides.

Welded back up with stainless wire and reassembled the heat shields before refitting.

Just got to finish the last of the tig welds to the 4th joint, so blowing a little, but couldn't resist a quick vid for you Chris_D.

I think it sounds awesome and can't wait to get out in it later..

Mike

woolybear · Post by **woolybear** » Thu Mar 30, 2017 1:58 pm

Sounds, damned epic

Cheers..

Ducklakeview · Post by **Ducklakeview** » Thu Mar 30, 2017 2:01 pm

woolybear wrote: ↑Thu Mar 30, 2017 1:58 pm Sounds, damned epic

Cheers..

Will tig the last joint once I've gotten the sprogs from school and get her out off the garage for another video.

Mike

lordgrover · Post by **lordgrover** » Thu Mar 30, 2017 2:49 pm

Ducklakeview, test only.

lordgrover · Post by **lordgrover** » Thu Mar 30, 2017 2:50 pm

Yep. Looks borked to me.

funksta · Post by **funksta** » Thu Mar 30, 2017 6:06 pm

It sounds great Mike . Try reving it with the sport button on you get a deep rumble and pops and bangs . With the sport button on , mine pops bangs and even cracks every time I lift off the pedal no matter what speed I'm going. Even the wife likes it .. I don't know if it's just me but I think it feels like there's more poke as well when I removed my secondry cats .

greg81 · Post by **greg81** » Thu Mar 30, 2017 6:23 pm

Sounds epic!

What are the downsides of doing this? Fail emissions tests?

Kbs133 · Post by **Kbs133** » Thu Mar 30, 2017 6:37 pm

Sounds great Mike.

Ducklakeview · Post by **Ducklakeview** » Thu Mar 30, 2017 6:41 pm

To be honest I think they do impede the flow a lot! When I cut them off, I put the airline in the end blew through, the back pressure forced my hand holding the blower away. After removal there was zero back pressure. Was going to use sleeves, but have ended up splitting the downpipe joint and removing back to the backbox joint. Just got to get it on the bench to tig it all up.

Mike

Ducklakeview · Post by **Ducklakeview** » Thu Mar 30, 2017 9:25 pm

greg81 wrote: ↑Thu Mar 30, 2017 6:23 pm Sounds epic!

What are the downsides of doing this? Fail emissions tests?

None!

The emissions are handled by the primary cats, and that's where the lambda sensors are. Removing the secondaries will still allow an mot pass.

Mike

greg81 · Post by **greg81** » Thu Mar 30, 2017 9:27 pm

Ducklakeview wrote: ↑Thu Mar 30, 2017 9:25 pm
greg81 wrote: ↑Thu Mar 30, 2017 6:23 pm Sounds epic!

What are the downsides of doing this? Fail emissions tests?
None!

The emissions are handled by the primary cats, and that's where the lambda sensors are. Removing the secondaries will still allow an mot pass.

Mike

Ooh, interesting

.

My insurance never asked any details of the mod when i signed up...

DMC63 · Post by **DMC63** » Thu Mar 30, 2017 9:40 pm

Do you get droning in the cockpit when at cruising speed?

MACK · Post by **MACK** » Thu Mar 30, 2017 9:41 pm

It will be interesting to see how it feels on the road, I would have thought it will feel a bit perkier and faster revving now.

Ducklakeview · Post by **Ducklakeview** » Thu Mar 30, 2017 9:42 pm

DMC63 wrote: ↑Thu Mar 30, 2017 9:40 pm Do you get droning in the cockpit when at cruising speed?

Yet to try it, but my exhaust mod doesn't drone and the cat removal just adds extra pop and crackle when accelerating, so I'm hopeful it'll be fine.

Won't be able to finish it until Saturday now add in the shop all day tomorrow

Mike

Ducklakeview · Post by **Ducklakeview** » Thu Mar 30, 2017 9:44 pm

MACK wrote: ↑Thu Mar 30, 2017 9:41 pm It will be interesting to see how it feels on the road, I would have thought it will feel a bit perkier and faster revving now.

That's why I've done it, more for performance than sound. And after I realised just how much back pressure they generate.....

Mike

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