Reworking Exhaust on an 86, Need Opinions
04-10-2005, 11:15 PM
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Reworking Exhaust on an 86, Need Opinions
There are 3 cat converters on my car. Should I chop the big main cat, run straight 3" pipe in place of it? Or nix the #" crossover pipe section and run true duals?
Or remove the two smaller pre cats? Catco makes part #3518 which does this. Nice simple bolt on, do-it-yourself.
I still have the AIR smog system (for now) can that pipe that come out of the cat be left there sucking normal air if the main cat is removed?
I'm trying to get the most bang/buck and still pass emissions.
Thanks.
Or remove the two smaller pre cats? Catco makes part #3518 which does this. Nice simple bolt on, do-it-yourself.
I still have the AIR smog system (for now) can that pipe that come out of the cat be left there sucking normal air if the main cat is removed?
I'm trying to get the most bang/buck and still pass emissions.
Thanks.
04-10-2005, 11:20 PM
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St. Jude Donor '05
More than likely you will need both precats and the main hooked up to pass the visual.
04-10-2005, 11:29 PM
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My guess is that as long as they see a cat (or two), it will pass visual. I know the LT1 and most later model Vettes from 91 and newer had true duals with a cat on each pipe, right?
04-10-2005, 11:48 PM
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St. Jude Donor '05
Not familiar with the LT1's arrangement. i know the L98 used 2 precats and one main
04-11-2005, 12:05 AM
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You don't say where you are located. If in California, removing any of the smog equipment will prevent you from passing smog. DMV randomly selects a large number of cars to be certified at test only stations where they go over your car with a finetooth comb as well as pass emissions while on the rollers. I suspect the rest of the country will follow suit shortly. In my opinion it just isn't worth the hassle of removing the smog stuff for the minimal gains. Yeh, I know, I'm to old, but much wiser. BTDT
04-11-2005, 09:28 AM
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If you remove the AIR, remove its piping.
I'd get rid of the precats and install a new main cat if thats a choice, like a Random Tech.
I'd get rid of the precats and install a new main cat if thats a choice, like a Random Tech.
04-11-2005, 12:42 PM
#7
Le Mans Master
If you decide to remove the precats, I would recommend you obtain an '85 headerpipe, then there will be no evidence that there ever were precats.
Ironically a friend took his '86 to Spain back in 1986 and had to remove all of the cats. When he returned he traded the car and the dealer wasn't interested in the cats, so he gave them to me. Another friend felt his main cat was bad so I gave him the main cat and within a year, he discovered it was really the pre-cats that were the problem. With a new (read good) main cat alone, you should have no difficulty passing emissions tests assuming the car is in good tune.
GUSTO
Ironically a friend took his '86 to Spain back in 1986 and had to remove all of the cats. When he returned he traded the car and the dealer wasn't interested in the cats, so he gave them to me. Another friend felt his main cat was bad so I gave him the main cat and within a year, he discovered it was really the pre-cats that were the problem. With a new (read good) main cat alone, you should have no difficulty passing emissions tests assuming the car is in good tune.
GUSTO