Blowing out bad cats

[Jefe]

6 months back I was driving through a freak rain storm and crossed through a street where water was a few inches deep. The next day I noticed a rattling on acceleration and proceeded to blow the catalytic converter material out the back. Quite a smoke show...

Friday I started hearing the same rattling so I figured more came loose. A few first gear pulls later another smoke show but it still sounded clogged. Ive put probably 40 miles on it since then with lots of first gear pulls and free revs and it wont break up.

Short of cutting the piping and manually fixing it what else can I try? And am I possibly causing any harm to the motor by trying to blow it out with pedal force? Obviously feels way down on power.

Haven't tried soaking the cats again so I may do that. Loving the deeper tone

 

[Jefe]

Some more blew out this morning. Still sounds a little clogged

 

[shurur]

well..it seems to me that eventually you're going to have to remove the midpipe/cats and bore/ramrod them out...or replace them.

They must be ceramic.


I take it that the chunks aren't making it through you mufflers?? If not..it can't be doing the mufflers much good.

I've read that ceramic last longer if not bumped..but with them at the botton of the car in the midpipe how can they not get bumped...then there is the spun metal supposedly not handling much heat....getting a good replacement that will last is the real challenge.

All I have is the original precats on mine ..ask me if I think my cats are junk by now.
I was going to gut my precats and put in midcats this summer...but not sure what empty precats off of stock headers would do for sound or power or exhaust...HMMM??..another thread.

somewhat related to your problem:
http://www.svtperformance.com/forum...replacement-cats-needed-bassani-catted-x.html

 

[po-po 5.0]

an '03 cobra should have metallic substrate precats and ceramic main cats. The metallic cats are tougher AND less restrictive.

 

[Jefe]

These were aftermarket Catco cats. More blew out this morning and it sounds like its all out now. Car is louder and gets into boost quicker. Woo hoo! Self gutted cuts!

 

[MysticRob]

Might want to stop where you're at before you do damage to the engine. Get the entire length gutted and cleaned out. There's no telling what chunks might get lodged along the piping to clog the exits and lead to increased back-pressure and heat.

 

[shurur]

an '03 cobra should have metallic substrate precats and ceramic main cats. The metallic cats are tougher AND less restrictive.

I'm guessing my 99 precats are old-tech ceramic...I'm moving to pypes catted mid-pipe then...sounds like Jefe should look at doing something similar...in leiu of ML/LT headers..for now..

Q: Jefe..what headers do you have? i.e Do you still have precats?

 

[Jefe]

Stock manifolds and just the Catco cats on a Bassani X pipe

 

[OW99]

Take the mid pipe off and smash it with a hammer until everything comes out.

 

[shurur]

Stock manifolds and just the Catco cats on a Bassani X pipe

I say walkers cats if you stay ceramic..rockauto

 

[BlueMonkey]

I had this same issue last month (as you noticed since you linked me to this thread).
I bought the magnaflow metallic substrate converter pn 59956 off egay for $89 ea shipped, but haven't had time to get by the muffler shop. I drove the car today and hopefully can get them welded in this afternoon. Will see how they last.....
A contributing factor to my blown-converter issues may have been that my exhaust hung pretty low-PO installed w/ clamps and I let it go instead of fixing. It scraped many times, both coming out of parking lots and occasionally at high speeds bottoming-out after intersections/rr tracks. :kaboom: Mine also blew chunks out of the exhaust. When my muffler guy re-hung the exhaust a couple weeks ago and inspected my old ceramic-style converters, he said one was missing a biscuit which he pulled out of my muffler. So while you may have been successful "blowing" it out, you may not have. Initially I thought I successfully blew mine out as well, but then I noticed an exhaust leak, which I believe was actually caused by the remaining biscuit in the cat become loose and re-lodging in a manner that impeded exhaust flow through the converter.
Anyways, will post back with initial thoughts on the magnaflows after they are installed.

 

[Jefe]

Well a bunch more blew out last night. A Mini Cooper was following me and unfortunately had the top down. She didnt look too happy lol.

No more rattles and much throatier exhaust. I kinda like it...

Planning on dropping the IRS soon for bushings so Ill take the X and Catback off and check in there for debris

 

[Jefe]

Got back from vacation and I had new rattles. Blew some out and now its officially clogged. Just limping the car around today. Called an exhaust shop and they want $200+ per cat and wont just cut them off until I can get some shipped(EPA fine of $2500)

Who makes a metallic cat that doesn't cost a ton? Found these:

http://www.jegs.com/p/Magnaflow/Mag...y-Metal-Catalytic-Converters/1250678/10002/-1

Found these as well. Anyone use them?

2 5" High Flow Performance Bullet Catalytic Converter | eBay

2 5" Thunderbolt Catalytic Converter High Flow Stainless Steel | eBay

2 5" Thunderbolt Catalytic Converter OBDII Heavy Load Late Models | eBay

I think I want to get away from ceramic because theres a good chance I may drive through water and melt the ceramic again. Pretty cheap above though

 

[Jefe]

Think Im going with these

2 5" Thunderbolt Spun Metal High Flow Performance Catalytic Converter New | eBay

 

[black4vcobra]

Off road midpipe not an option?

 

[Jefe]

I am catless now, just had them cut off. Gonna try it for a bit and see how I like it. Its so loud muahahaha

Did throw a code(P1405 I think) and it looks like my DPFE hose blew off from the pressure of trying to blow them out. The leak sound is coming from the firewall right above the gas pedal it seems. So tight in there I couldnt see any hoses that popped off though. Anyone have a pic of this hose? Easy fix? I read some guy had theirs melt. Guess Ill stay out of boost in the meantime. Sounds like some put a clamp on it

 

[Jefe]

Just went out and checked and the hose to the middle port or the port closest to the sensor is missing. Cant find a loose hose though. Hmmm

 

[Jefe]

Wow, our cars are loud without cats lol. Nice change but I dont think I can do this for much longer. Insanely raspy at WOT. Cruising tones are amazing with the Borla Stingers.

Wound up ordering the Thunderbolt metal spun cats from ZZ Performance. I emailed him and he knocked off $10 so it came out to $130 shipped for metal spun cats. They also have stainless steel too. Paid 2 hours ago and already have a shipping notification