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Replacing 02 simms, going with a cat, need opinions

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Old Mar 28, 2002 | 12:11 AM
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Default Replacing 02 simms, going with a cat, need opinions

Ok, I have posted this to my local board (In town) and am gonna post it here to get some feedback. Any feedback would be appreciated.

This is after getting f'ed up reading on diagnostic computer and auto tap

Welp Here are the results... I ended up getting the Computer replaced today. Free of charge (dont ask). There was high voltage going to the computer , therefore kinda frying it. There was also corrosion buil up from the wire to the computer. That was cleaned up and new computer was put on. The simms have been taken off and regular sensors hooked back up. The diagnostic reading turned out to be normal after everything was swapped, however the SES light will still be set off soon cause i still dont have cats. What I am gonna go ahead and do is have a cat (1) put on tomm. for $160. The guy told me it was a 2 chamber (3 inch)cat and should give good readings after installation. Just wondering if yall had any thoughts, cause it is a little starnge I am just having one put on as opposed to 2. So instead of having 2- 2.5 inch cats, I am having 1- 3 inch cat put on. (past the Y-pipe). Sound strange?
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Old Mar 28, 2002 | 02:26 AM
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Default Re: Replacing 02 simms, going with a cat, need opinions

That's a different approach. I wonder what the performance difference will be. Let us know what you think.

My gut feeling is that two 2.5 inch cats in parallel is less restrictive than one 3" cat, but there is already the 3" pipe, so who knows?
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Old Mar 31, 2002 | 09:07 PM
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Default Re: Replacing 02 simms, going with a cat, need opinions

I was always of the opinion that putting your cat that far back in the system (i.e. after the Y-pipe) may prevent it from heating up properly thereby making it less effective. Also, if you are running a rear O2 sensor behind the cat it may not heat up properly either. I think Bosch and maybe others make a heated O2 sensor if that does become a problem.
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