88 cat delete?

[rangeron33s]

what needs to be done with the O2 sensor to not throw codes when perminatly removing the catalytic converters? also thinking about a possibly attempting a complete emissions delete. any suggestions?

 

[adsm08]

any suggestions?

Don't eff with the emissions system.

 

[dave2575]

A few years ago I hollowed out both my cats and then welded a strait piece of pipe inside both of them to have a strait exhaust to the muffler. I ran it that way for a little while. At first it ran better than ever and without issues. Later I started noticing some issues, the 2.9's power was erratic, the idle would jump around, I also noticed my mpg were lower than usual and It would throw codes. I didn't do anything about my o2 sensor, I just left it there witch is why It would throw codes. All that went away when I put on my "bi-yearly once a day" cats, you know my "damn, I need to pass smog this year" set of backup cats ;-}.
The 2.9 will run better with the cats rather than deleting them all together.

 

[exbass94]

What are you hoping to accomplish by removing the cats? You're not gonna get more power; it won't do anything except pollute more. Frankly I think it's very inconsiderate when people want to remove cats. We ALL have to breathe the same air. So, thanks for making me breathe your filthy exhaust. Thanks a lot.

But to answer your question, removing the cats on your truck shouldn't throw any codes. Are there any o2 sensors downstream of the cats? I'm 99% sure there aren't. If there aren't any, there's no way for the computer to know they're functioning.

 

[RonD]

The '88 is an OBD I system, most OBD I only have O2 sensor(s) on the exhaust manifold, or "Y" pipe, so only pre-Cat(upstream).

OBD II is when they added an O2 after the Cat to monitor it's ability to reduce HC in exhaust.

And as stated by previous posters, removing the Cat is a bad idea, unless it is collapsed, then you should replace it.
Exhaust systems are often misunderstood, people see racing cars with straight exhaust systems, no muffler or Cat, and think that just removing these will increase performance.
That is untrue.
Those are TUNED EXHAUSTS, the pipe size and length FOR EACH CYLINDER is calculated to give the correct amount of backpressure(yes, back pressure is GOOD ), for the power band they want, low, mid or high range.

Your current exhaust system has been calculated to give the best performance in the mid-range power band, WITH Cat and muffler, assuming both are in good condition.
Some change to headers and if they are the correct ones for the engine you can move the power band lower or higher, no increase in power it just moves it to a lower RPM or higher RPM, that's the point of headers

EGR system doesn't "rob" power, it actually helps to keep cylinders from pinging under heavy loads, so increases power by preventing pre-ignition.

 

[rangeron33s]

Thank you for the help. Yes there's only one o2 sensor so I didnt think it would throw codes but I'd rather be safe than sorry. And I was wanting to run a true dual setup with flowmaster super 40s to the axle. But didnt want to have to deal with putting cats back on. On the otherhand what should I do with the original O2 sensor? Should I just put it on one of the pipes somewhere? Or should I just disconnect it all together?

 

[kimcrwbr1]

It is against federal law to remove cats big fine if you get caught number one. It is just a 2.9 correct it will never sound like a V-8 number two. You want noisy do a 5.0 swap.

 

[adsm08]

The fact of the single O2 sensor and my truck being a 4x4 kept me from ever attempting a true dual exhaust. Frankly, in all the exhausts I ran the best sounding one was all but stock. I replaced the stock muffler with Thrush and poured some kerosene in it before installing it, it will "modify" the sound absorbing effects of the fiberglass and make it a bit deeper.


As for a total emissions delete on an 88, well all you have is the cat and the EVAP system. The evap system just traps the fuel that evaporates from the tank while the vehicle is sitting and stores it so it can be used later. Why would you ever want to get rid of that?

 

[kimcrwbr1]

Also the only thing that cools the valves is fuel and when you reduce backpressure you risk burning valves as well!

 

[RonD]

Thank you for the help. Yes there's only one o2 sensor so I didnt think it would throw codes but I'd rather be safe than sorry. And I was wanting to run a true dual setup with flowmaster super 40s to the axle. But didnt want to have to deal with putting cats back on. On the otherhand what should I do with the original O2 sensor? Should I just put it on one of the pipes somewhere? Or should I just disconnect it all together?

Yes you need the O2 sensor for the Fuel injection system, so it must be reinstalled, either bank will be fine but..............could end up with a lean or rich condition do to injector issues on the unmonitored bank.
The O2 will set the fuel/air mix based on just the one bank

 

[simpler=better]

Keep the cat. Moving to a "spun" converter immediately off the manifold helped my truck run better.