cat. converter

[88capriceclassic]

1988 V8 305 4bbl.

okay well my catylatic converter has been makin some wierd noises and smells and i think its clogged and ready to blow or something so im gonna take it off and put a straight pipe through it but i need to know how many inches long and what quarter inch it is.i think i know how to figure how long i need it to be by using a tape measure from bracket to bracket but i dont know how big a' round it is.if anybody has had theirs taken off and know please share info me and the procedure of how to do it.thank you all.

[silicon212]

Originally Posted by 88capriceclassic

1988 V8 305 4bbl.

okay well my catylatic converter has been makin some wierd noises and smells and i think its clogged and ready to blow or something so im gonna take it off and put a straight pipe through it but i need to know how many inches long and what quarter inch it is.i think i know how to figure how long i need it to be by using a tape measure from bracket to bracket but i dont know how big a' round it is.if anybody has had theirs taken off and know please share info me and the procedure of how to do it.thank you all.

Before you take it off and replace with straight pipe, I'd double-check the emission laws where you are. You can get a bolt-in replacement converter at Autozone for around $65 or so. Chances are the input pipe and output pipe are different diameters.

[bobss396]

Your car may run worse without the cat. Of course if the overall running condition of the motor is poor, you may not notice much of a difference.

I did a cat change on my '84 last year and it made a huge difference in how the car runs. At 153k miles, it runs smoothly and has a lot of power, plus it complies with the local emissions standards.

Bob

[88capriceclassic]

yea i live in kansas and they dont do emission tests but in missouri they do and thats where my car use to be in the lake of the ozarks. but if i buy a new cat then how long is it goin to last before it gets bad? and i have also heard that a straight pipe through increases horsepower a little or something. currently the only problems my car has are carburater troubles but i dont know engine troubles yet cuz i havnt had much.

[silicon212]

The biggest cat-killer is a rich running engine. Leaded gasoline used to be lethal to a cat too, but nowadays you cannot get leaded gasoline. If the engine runs rich, that causes the cat to overheat and burn out. A rich running condition also will lead to premature EGO sensor failure. Bad timing or burned valves can also lead to a failed cat due to backfiring.

If you keep the mix correct (always make sure your air filter isn't plugged, and repair any carb problems), and ensure the engine is kept in tune, the cat should last years. They're warranted for 5 years as required under federal legislation.

--

In the subject of power loss/gains with or without the cat, there used to be truth that removing the cat can increase horsepower - but this was largely during the 70s when cats were filled with pellets. These cats were restrictive. The cat in your car is a low-restriction honeycomb monolithic design and putting one on won't hurt engine performance really at all.

[RodCar]

I work for a company that designs CC and cars were designed to use converters, I mean that is proved that if you eliminate the CC you are eliminating a "restriction" of the exhaust (increasing gas velocity) and some sensors, like the oxygen cannot work with gas flowing at different velocoties, also the engine will work cooloer and gas consumption will rise.

[bobss396]

I used to think that all emissions equipment was bad and took it off a few cars. It was ok until I came up with one that wouldn't pass emissions without it. As others suggested, get your carb problem straightened out, I had mine done locally for around $250 and it works well. The cat ran me about $120 with the tube kit, took about an hour to change. I had the AIR system manifold tubes done a few years back too.

While I'm not exactly an environmentalist, I feel it's up to me to have a car compliant with the emissions standards, just doing my part. Plus it's a case of the state wanting to get old cars off the road and me saying "up yours" to that.

As a result, the car idles fine, runs fine, has plenty of power, is quiet and doesn't do anything funny. I take it anywhere, anyone can jump into it and drive it.

Hope we helped, good luck.

Bob

[TommySS]

The federales expect the car to be emissions compliant. Penalties are pretty stiff.

[88capriceclassic]

no emissions tests in kansas.....

[silicon212]

Originally Posted by 88capriceclassic

no emissions tests in kansas.....

TommySS is right, fines can range up to $25,000 and higher - however these usually apply to garages and people who fix cars for a living and not the backyard mechanic working on his/her own car.

[CD Smalley]

Hey 88, Where in KS? I'm in the Wichita area.

[88capriceclassic]

i live in KCK in turner almost on the line of argentine.