[NightRydaSS]

Originally Posted by 96LT1Formula

welkl i jsut called pacesetter.. then dont offer a catted y.... they said that the mid length accomodate to the stock cat location.. how can that be so when the driver side cat is right under the manifold????

The mid length tubs are the same size and shape as the stock manifolds. It gives you better exhaust flow, while still being able to keep the Cats in the stock locations. It is illegal to move cats from their stock location OR replace a known working cat. That is why longtubs are "illegal" for our cars, since we have to move the cat to where the y-pipe is. Most catted-y's are "high flow", which is less efficient and there for you prob wont pass emmisions with your car, you have an OBD-I diag port so they require your car to be put on the rollers. LS1's have an OBD-II port, so as long as they see the cats and there is no "SES" light on the dash, and the computer says everything is ok, LS1 cars are normally good-to-go.

I did research, and mid-length headers are really no better then ur stock exhaust manifolds. The "bottle-neck" is the stock cats, so no mater how much the mid-length tubes flow, the end result is the exhaust isn't flowing anymore faster or with more volume out of the car then the stock cats are gonna let it. All u did was move your bottle-neck from you manifolds to ur cats. if you put on a free-flow exhaust (i.e Magnaflow, Borla, SLP Loumouth I & II ) ur removing 1 of 2 bottle-necks. if you want headers, do longtube, if your worried about inspection, replace your cat with an OEM one and get a free-flow exhaust.

Originally Posted by 96LT1Formula

i think i came to the conclusion im gonna buy the magnaflow direct fit cats.. but it says in the notes for the driver side "no provision for 02 sensors"... what does that mean???

That means there is no O2 sensor "bung" (the hole the O2 sensor screws into) on the unit. I think our cars have a total of 4 O2 Sensors. 1 before and 1 attached to the cat right behind the "honey comb" on each side.

I would stick to OEM cats and forget the "high-flow" ones. High-flow cats don't flow that much more then OEM. OEM ones aren't as restrictive as most people think. I didn;t believe it myself until i did some reaserch and saw flow comparison charts from un-biased ppl. You will also notice that some cats say OBD-I & OBD-II compliant. That just states it shouldn't set off the SES light on your dash; that it is compatiable with your computers stock settings. That DOESN'T mean it will pass emisions. Save urself the headach.