cutting catalytic coverter ?

[df2x4]

My vote is keep it. Nothing like stinky hydrocarbons flowing back into the cab or getting sucked in through the HVAC system when the wind is blowing the wrong direction. That stink permeates your clothes & sticks with you... Walker makes good highflow replacements. Where are the dyno results which support these claimed gains

Every time I drive my Monte Carlo I kind of wish it had cats. Love that car, hate the way it makes my clothes and garage smell.

 

[DerekTheGreat]

Every time I drive my Monte Carlo I kind of wish it had cats. Love that car, hate the way it makes my clothes and garage smell.

I hated my '69 Fury for that reason. Working on it for any length of time instantly made me stink. Hell, driving it made me stink. Like why bother taking a shower? LoL...

 

[Iowan]

My vote is keep it. Nothing like stinky hydrocarbons flowing back into the cab or getting sucked in through the HVAC system when the wind is blowing the wrong direction. That stink permeates your clothes & sticks with you... Walker makes good highflow replacements. Where are the dyno results which support these claimed gains

That's what keeps ya going!!

 

[ima93chevyguy]

I cut mine off several years ago, smells pretty bad lol... I probably gained a little HP and some MPG but mine wasn't blocked or anything so it was pretty minor. Full exhaust rework would be 100x better.
Everyone i know says it smells like a "V8" or "Horsepower"

I would recommend a high flow cat, you don't lose performance and you don't get the smell. If/when i redo my exhaust i'm definitely going that route.

 

[Jay33089]

My vote is keep it. Nothing like stinky hydrocarbons flowing back into the cab or getting sucked in through the HVAC system when the wind is blowing the wrong direction. That stink permeates your clothes & sticks with you... Walker makes good highflow replacements. Where are the dyno results which support these claimed gains

I agree with this! When I LS swapped my truck I didn't put cats back on it. I'm thinking of having the exhaust re-done later this year with a dual in dual out muffler for balance.(kinda like a "H" pipe, right?) Anyway I'm strongly considering putting some high flow cats on. You can't stand close to it long with it running without it making your eyes water! Not to mention the smell!

 

[cnowalk]

My vote is keep it. Nothing like stinky hydrocarbons flowing back into the cab or getting sucked in through the HVAC system when the wind is blowing the wrong direction. That stink permeates your clothes & sticks with you... Walker makes good highflow replacements. Where are the dyno results which support these claimed gains

For the fun of it, my last few tanks have been ethanol free gas. I’m not 100% sure, but I think it’s made my exhaust a bit more tolerable. Still stinks and still sticks to clothes though, but it’s not burning my nose anymore.

 

[someotherguy]

I had a 95 k1500. I gutted the converter. Helped tremendously with fuel consumption and power. Check engine light never came on. It shouldn't on a 95 as they are TBI and only have one O2 sensor on the driver exhaust manifold.

I'd say I gained at least 3 mpg, but mine was crumbling and was blocking the air flow. As @jkeaton said most of the time there's not a real big gain in mpg's and power. As old as the cat is there is a possibility that it's beginning to crumble. If you can get to it shine a light inside and see what it looks like. If it looks clean and you can clearly see the honeycomb, then it's probably ok. If not and it looks like it's falling apart, gut it.

LOL...when suggesting someone should remove their cat because you say it helped tremendously with fuel consumption and power, you should tell the whole story in the first message - where your cat was bad and causing a blockage. Because otherwise it's pretty misleading..

Removing your cat IF it is not broken up and flopped over restricting the exhaust, isn't going to significantly improve power or fuel mileage. It will seem more powerful because it'll be louder, that's for sure.

If your engine is stock or near stock leave the cat in place. If you've built any reasonable amount of extra power (heads, cam, stroker, tuning to support the changes, etc.) then consider high flow...

Richard

 

[someotherguy]

Plan and simple fact, proven many a many time in many differant places...... the age old, cat no cat discussion...

If your cat is not clogged and or melted(caused by an engine issue to begin with as they do not melt or clog for no reason on their own) it will NOT hurt your mileage and or backflow and or performance.

Sent from my SAMSUNG-SM-G891A using Tapatalk

I did bust a couple out because they had come apart; one had lodged a huge chunk sideways into the inlet of my muffler. Not cool!

Richard

 

[someotherguy]

You can't stand close to it long with it running without it making your eyes water! Not to mention the smell!

Your truck is running far too rich. Properly running, no cats, should not be that intolerable to be near.

Richard

 

[Jay33089]

Your truck is running far too rich. Properly running, no cats, should not be that intolerable to be near.

Richard

It may be. Just has a mail order tune in it now. I'm still studying my HP tuners software. I haven't worked up the nerve to try tuning it just yet. It could be rich, but it runs great. I'm currently getting 13-14 mpg around town and 16-17 mpg on the highway. Considering the max 10 mpg it was getting before I'm in heaven! I know the issue before was leaky poppets on the spider but never got around to fixing it before the swap.