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Old 09-10-2001, 08:58 PM   #1
worldofme
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Join Date: Sep 2001
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Post exhaust leak

couple questions about exhaust leaks and exhaust sytems.

first off, I'v got an exhaust leak somewhere near the exhaust manifold and after replacing the exhaust manifold gaskets I'm still getting a leak and can't quite pinpoint it's location. I noticed a leak under the valve cover and I'm wondering if it's possible that leak could be making the noise that sounds like an exhaust leak?

I have dual exhaust on my truck and each side runs straight from the exhaust manifold, down to a muffler then down the rest of the truck. I've been told that on dual exhaust I need an exhaust pipe connecting the two and I want to know if this is true?
Also, I don't have any catalytic converters on either side and have been told in some cases they aren't needed but I live in California where smog checks are required. Do I need them and if so do I need one for each side or just one on one side?

this is all for a 1977 Chevy K5 Blazer 4x4 350cbi. Any input would be greatly appreciated. Thanks
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Old 09-11-2001, 12:37 AM   #2
Z16
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I've never heard a valve cover leak make any noise. Maybe a slightly loose rocker? A well designed X style crossover will make quite a difference on a dual exhaust, but just sticking in a crossover probably won't, but can't hurt. A good performance oriented muffler shop can build what you need. With dual exhaust, you will need one converter on each side. You can buy free flow ones that won't effect performance at all. What is the cutoff year for emissions in Cali? Can't remember if it's 25 or 30 years old. If it's 25, you won't need any converters next year, although as you can get some good ones, I would run them just do do your part for the environment.

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Old 09-11-2001, 12:51 AM   #3
68SWB4x4
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its 73 and older dosnt need smog.... so 77 needs smogg... and im not sure when cat converters were put on these trucks..... but if your truck wasnt factory equiped with them it dosnt need cat converters

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Old 09-11-2001, 11:50 PM   #4
Longhorn Man
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Problem with putting 2 verters on it is that even though it will be cleaner, it is still considered as emission tampering. Go to a smog station and get the info from someone who is paid to send you home crying. If I am right, you'll have to get a verter that has 2 inlet and 2 outlet in order to have true dual exhaust. It'll need to be mounted in the stock location too. Tampering is just as bad as removing as far as the law goes...$2500 bucks either way if they fine you.
I dunno when verters were required on trucks, I know '75 for cars though.

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