longtubes on 01 MN6 question
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From: New Jersey
longtubes on 01 MN6 question
Hopefully with a little cooperation from mother nature next week my car is going to East Coast Supercharching for headers - hi flow cats and x-pipe, plus a rear gear change. My question is will the longtube headers and hi flow cats ommit the need for pup cats? My understanding is that they were only needed for 00 and 01 until they came out with a new material used in later cats that didnt need pre heating. So I'm hoping to eliminate them with no ill effects to emissions! Any help would be appreciated 
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From: I love you & miss you Linda
2017 C7 of the Year Finalist
St. Jude Contributor
With Long Tube headers, the only cats you will end up with are the Hi-Flows that you bought and are having installed.
The small cats that are on the down stroke of the pipes just after the now existant exhaust manifolds will be thrown in the trash to never been seen again (along with the old exhaust manifolds).
The headers will eliminate them completely.
You do NOT need them.
Your car not only will run better but your inside temps will be reduced too. The one small cat is right next to your right foot when driving, heating the inside of the car up....
Your car will be fine after those guys at ECS are done with it.
The small cats that are on the down stroke of the pipes just after the now existant exhaust manifolds will be thrown in the trash to never been seen again (along with the old exhaust manifolds).
The headers will eliminate them completely.
You do NOT need them.
Your car not only will run better but your inside temps will be reduced too. The one small cat is right next to your right foot when driving, heating the inside of the car up....
Your car will be fine after those guys at ECS are done with it.
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From: Gone
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St. Jude Donor '03
Yes, longtubes will eliminate the pup cats, and no, they aren't needed.
The pup cats were only used to satisfy strict CA emission requirements. On the early year C5s, there was a "CA emissions" option (YF5), that included the pup cats if I'm not mistaken.
When it became mandatory that the Corvette become a "50 state" (LEV) car sometime in 00, meant the rest of the 49 states got stuck with the pup cats too.
The pup cats were only used to satisfy strict CA emission requirements. On the early year C5s, there was a "CA emissions" option (YF5), that included the pup cats if I'm not mistaken.
When it became mandatory that the Corvette become a "50 state" (LEV) car sometime in 00, meant the rest of the 49 states got stuck with the pup cats too.
