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Old Jun 25, 2006 | 10:59 PM
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Default 1 cat with long tubes

Could you pass emitions with long tubes and one cat after the y-pipe?
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Old Jun 25, 2006 | 11:23 PM
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No....
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Old Jun 25, 2006 | 11:25 PM
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that's a double no...
lt's = fail visual (depending where you live)
1 cat = fail visual (depending where you live)
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Old Jun 25, 2006 | 11:31 PM
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Plus the cat will be too far back to perform it's proper function.
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Old Jun 26, 2006 | 03:40 AM
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Originally Posted by NHRA Trans Am
Could you pass emitions with long tubes and one cat after the y-pipe?
It might pass a sniffer test, but it wouldn't be as efficent. It would certainly fail visual.

But worst of all it'd choke the engine. It would totally negate having done any work on the exhaust at all and even with headers you would probably have a worse performing exhaust setup than stock.

2 Cats, one per banj is the way to go. Cammed/bolt on LS1's are fine with Mahanflow Carsound £2 core CATS.

More extreme setups would want Metal Matrix 3" core setups from Random Technology or Magnaflow.

If you're in CA it's a different story however, as LT's aren't legal.
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Old Jun 26, 2006 | 08:07 AM
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lol 1 cat serves no purpose performance wise, sound wise or emissions wise. it's a lose-lose
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Old Jun 26, 2006 | 09:16 AM
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Thanks for all the help, I guess i will be running 2 cats.
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Old Jun 26, 2006 | 11:53 AM
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Originally Posted by NHRA Trans Am
Thanks for all the help, I guess i will be running 2 cats.
First of all, where are you located? I thought of running LT's with cats at the collector, until I realized I would fail the ish out of visual in California, and probably fail the hell out of the sniffer test too. The smog ref said you cannot move the cats from their stock location and pass visual, period, they are put in that position for a reason, they have to be heated to a specific temperature to function correctly. Moving them back will cool them down and become less efficient. I said the F with it and yanked them off, ran an ORY and paid some guys to pass me (which is ridiculous btw). Smog for me is coming up in November, not looking forward to paying big bucks AGAIN with the turbo setup. I hate smog...
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Old Jun 26, 2006 | 12:43 PM
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run cats. nearly every exhaust on an LS1 sounds better with them. if this were a mustang forum i'd say go ORY, but it's not
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Old Jun 26, 2006 | 08:40 PM
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are lt illegal in md
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Old Jun 26, 2006 | 09:53 PM
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Originally Posted by 300bhp/ton
£2
What kind of keyboards do you have over in England?
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Old Jun 26, 2006 | 09:54 PM
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Originally Posted by bad6as
are lt illegal in md
Not illegal persay, but not legal for street use.
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Old Jun 27, 2006 | 05:14 AM
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Originally Posted by orangeapeel
What kind of keyboards do you have over in England?
Doh!

Standard UK layout QWERTY keyboard

This is totally user Error! I meant 3" which is the nummber 3 key and shift number 2 key for the " inch symbol. However I must have held shift down when I pressed the number 3 key which gave me the pounds Sterling £ symbol.
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Old Jun 27, 2006 | 05:18 AM
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3 = # here.

I didn't know if you went and found that on a character map or if it was indeed on your keyboard. Cool fact.
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Old Jun 27, 2006 | 05:21 AM
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Originally Posted by orangeapeel
3 = # here.

I didn't know if you went and found that on a character map or if it was indeed on your keyboard. Cool fact.
Yeah UK layout is slightly different to US, but mostly on special characters. It's a PITA if some numskull has installed Windows and left the default as US layout.
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Old Jun 27, 2006 | 05:21 AM
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Originally Posted by 300bhp/ton
Yeah UK layout is slightly different to US, but mostly on special characters. It's a PITA if some numskull has installed Windows and left the default as US layout.
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