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Goodbye to the cat?

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sparkydave

sparkydave

Jedi Knight
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Normally I lean more towards the notion of keeping the emissions controls present on the car, even if though I'm exempt from emissions requirements, but I'm thinking of replacing the catalytic converter with the regular exhaust header for two reasons. One, I've heard stories of the converter getting hot enough to melt plastic parts of the carburetor, and two, I seem to have trouble with vapor locking when things are hot. Well, this weekend the carburetor heat shield broke on the car, and a buddy of mine thought that removing the catalytic converter might help the exhaust flow a little more freely, as well as helping the vapor lock problem. Anybody have any thoughts on how performance will do without the converter? My guess is that things will improve. It would also be nice not having to keep nursing the throttle after starting the hot engine to keep it from stalling.

-Dave
 
Hi Dave. Just my few cents, but I intend on losing my cat too. I'll have relaxed emissions standards here in Nevada due to the age of the car, so if I get it tuned right, it should still pass smog. I had to cut the bolts off of the exhaust manifold yesterday with a torch to get the thing off the car. My car has Cali emissions, so by losing the cat, I can also lose the air pump. I expect to see some improved performance due to better flow of the exhaust and no air pump dragging on the engine. As for the heat shield, only my guess, but it's there primarily due to the heat of the cat. No cat, no heat shield, although I'm probaby going to keep mine on my car anyway.
 
I have my cat removed, as well as all the emissions equipment. I would never do something like that to my daily driver, but I justify it with my midget because of the amount that I drive it (not much, relatvily), and the way it runs without it. My midget runs great! My ZS is nicely tuned, and I keep everything fresh (plugs, filters, oil, etc). I am by no means an engine perf expert, but I know that my midget runs great, smooth and reliable, with no stalling problems at all in the 5 years that I have owned it (the P.O., who is my cousin removed the cat and emission equipment.)
 
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