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Catalytic Converter

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Atrus

Atrus

Jedi Warrior
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I'll probably rile some people up here ;), but has anyone ADDED a catalytic converter to their LBC?

I am 110% sure mine is <u>not</u> tuned perfectly, but I think it's darn good...and I get tired of smelling like exhaust fumes when I get out of it. Don't get me wrong, I like the way non-emissions cars smell, but I don't care to drive the LBC to a friend's or something and smell all evening.

Just curious if anyone else experiences this, and especially if anyone has added one. I think one may be in my future!
 
Your tail pipe is too long prob.
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]and I get tired of smelling like exhaust fumes when I get out of it. [/QUOTE]
Then you are NOT "tuned" correctly OR have an exhaust LEAK or BOTH, Kevin!! /bcforum/images/%%GRAEMLIN_URL%%/hammer.gif

I drove my '63 BJ-7 Austin-Healey(Hortense) to my wedding, bride was delivered to church in her '73 Black Tulip MGB(Murial) and several other folks came with a various LBCs and the half of the group that did NOT come in LBCs had NO "comments" about "smelling" the LBC folk!! /bcforum/images/%%GRAEMLIN_URL%%/angel.gif

I also drive my '70 QuadraJet Carbed El Camino DAILY with NO "aroma". /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
/bcforum/images/%%GRAEMLIN_URL%%/cheers.gif
Ed
 
I am all for Catalytic converters. The big question is where do you put it. My 79 originally came with a small cat attached directly to a short exhaust manifold that was broken into 3 parts when I got the car. As almost every post 78 Midget exhaust manifold that was made is now cracked or broken, it was not possible for me to replace with an OEM manifold on my budget. Thus I purchased an affordable pacesetter header. However, with the header there is now no convenient place to put a cat. The header is too long to allow installation of a cat in the engine compartment as original, and the smallest one I could find was 4" think, do mounting beneath the car is right out. I finally bought a small after market cat which I relocated to sit just in front of the rear axle. This was before I new much about how cats work, so I think I probably wasted my money as the cat is too far away from the engine to get hot enough to function properly.

If anyone else has any ideas on where/how to mount a cat, I will be interested in hearing them.

And I am guessing Ed's diagnosis is spot on.
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]As almost every post 78 Midget exhaust manifold that was made is now cracked or broken[/QUOTE]
I didn't know that - I have several good used ones!
 
Hmmm...maybe I'll have to play with the settings more once the weather breaks here.
 
Check also that your exhaust pipe is not to long or has a fancy tip on it thus pulling exhaust back into the car. It should be just even with the bumper, no longer.
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]I didn't know that - I have several good used ones![/QUOTE]

Tony, I don't think I knew you when I was looking for that exhaust manifold. Now that I do, maybe I will take one of those manifolds off of your hands. /bcforum/images/%%GRAEMLIN_URL%%/wink.gif
 
How about just not use the darn thing.
 
Donn, that's what I did. Not sure if it works or not, but I had a recent exhaust leak just before the cat and the air coming out of the leak did not seem very hot.

Kim and Jack, sorry to say that I disagree with you. Actually, the cat does not work at all when the engine is cold, because it must warm up, too. There are many times when the cat does it's job through out the driving range, like during acceleration, idle and deceleration: all times when a well set up car runs rich. My car is a daily driver, not a weekend runner/show car. I would feel guilty if I did not make every reasonable effort to reduce the stink I am putting out into the air.
 
Maybe yours stinks but Miss Agatha is a lady of the old school, hehe.
 
Morris said:
Donn, that's what I did. Not sure if it works or not, but I had a recent exhaust leak just before the cat and the air coming out of the leak did not seem very hot.

Kim and Jack, sorry to say that I disagree with you. Actually, the cat does not work at all when the engine is cold, because it must warm up, too. There are many times when the cat does it's job through out the driving range, like during acceleration, idle and deceleration: all times when a well set up car runs rich. My car is a daily driver, not a weekend runner/show car. I would feel guilty if I did not make every reasonable effort to reduce the stink I am putting out into the air.
Click to expand...
Actually, yes you are right. The cat must get hot first, but with a good setup if won't be needed that much. You can adjust your idle mixture and get your jetting right and then the cat will be used when there are sudden changes due to accel or decel or a hard pull. Lots of extra heat under the floor of the car though. Also, if you are going to read your co emmissions or whatever to see how rich you are running, you have to do that without the cat on it. I tried my gas tester on my kia sportage and it always read perfectly low when I knew this was not the case. The cat was burning the excess co and fooling the machine.
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]I tried my gas tester on my kia sportage and it always read perfectly low when I knew this was not the case. The cat was burning the excess co and fooling the machine.[/QUOTE]

Hey, at least your cat is doing it's job even if your O2 sensor isn't. :wink:

I can't speak for an A-series, but a 1500 will not idle for poop on a mixture leaner than about 13.5:1. According to what I have read, this is true for most older cars. 13.5:1 is not terrible, but if you end up idling in traffic a lot, that really adds up. If you don't drive your car very much, it doesn't really matter.
 
Kim. That is proof in itself that the cat is working all the time. (except when cold)
They must be hot to work. But after that a carbureted engine can not keep the fuel mixture to stochiometric, causing ineffective cat operation.
On a lighter note, the cat is not the method to use to get rid of the stinky exhaust. that could be done with good mixture control and proper timing.
 
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