Cat or no Cat?

[cdslyde]

Pellet-style catalyst. Moderate chance there's no pellets in it any more. Used to see cars with pellet cats occasionally spitting beads out the tailpipe after they've gone through the exhaust pipe, muffler, and tailpipe.

The pellet-style cats were restrictive when new. Modern cats are honeycomb/monolithic and not as restrictive.


Illegal--violates FEDERAL law. The only thing you have going for you is that there's little enforcement unless the State or County does it.

It's also going to be a D-I-Y project, no decent shop will touch a catalyst delete as it carries a potential $10,000 fine--and there IS enforcement on that, although it's spotty.


Possible. Not popular. Both pipes need to go down the right side to avoid the transfer case and fuel tank. There are dual-exhaust, twin-catalyst systems for certain vehicles/certain engines in GMT400 trucks--but you're locked-out of that as you can legally only put one cat under your truck.

You might as well cram a high-flow "Y" pipe, high-flow catalyst, and big pipes back to the muffler and tailpipe.
www.summitracing.com/parts/jba-2831sy

JBA Performance Exhaust 2831SY JBA Performance Exhaust Y-Pipes | Summit Racing

Free Shipping - JBA Performance Exhaust Y-Pipes with qualifying orders of $109. Shop Exhaust Pipes, Y-Pipes at Summit Racing.

www.summitracing.com

1989 doesn't have rear/downstream O2 sensor(s).


1989, TBI.


Yup. But it's a single catalyst.


It's been so long since cars didn't come with catalysts, that when they're disabled/removed/defective, folks aren't used to the stench.

I went dual exhaust off of headers with no cats on my 82 vette that a shop did here locally.

 

[cdslyde]

I went dual exhaust off of headers with no cats on my 82 vette that a shop did here locally.

Regarding the pellet style cat you mentioned, is that what GM used in 1989? If they lose pellets, wouldn't that make them less restrictive?

 

[kennythewelder]

Yeah, I missed the 89 part. No rear 02 sensors till 96, your rite.

 

[kennythewelder]

82 Vette huummm, hers my 79

You must be registered for see images attach

 

[99xcss4]

gm pellet/bread loaf converter

You must be registered for see images attach

 

[99xcss4]

if you are going to run a cat or cats for duals https://www.ebay.com/itm/1262150788...mxijZF5OPjBHZk4i/RXvuIjro=|tkp:Bk9SR5j4v_iRYw

 

[cdslyde]

82 Vette huummm, hers my 79

You must be registered for see images attach

Nice looking vette!

 

[cdslyde]

gm pellet/bread loaf converter

You must be registered for see images attach

That doesn't look like what I have, so probably someone already swapped it out and put a honeycomb style in there.

 

[Erik the Awful]

Part of "not getting our hobby banned" is being honorable and doing the right thing. WCJr came to me straight-piped, and I spent the money to put cats on it. Roscoe was straight piped as well, and when I build the exhaust for it, it will have cats as well.

 

[someotherguy]

Fed laws aside, those of y'all complaining about stinky non-catted exhausts don't hang around enough classic cars. Just sayin'

On the flipside, I absolutely cannot stand the utter STINK of modern catted vehicles when they mash the pedal on the freeway. It smells like ammonia.. reminds me of when we'd go to pickup my grammaw at the hair salon, the chemicals they used to give the old ladies their perms. Awful.

Richard