[BunnyBoy]

Have a 2017 ZL1. Recently obtained Kooks 1 7/8 coated headers ONLY for a really good price(No off road X, or Cats).



I'm trying to understand what I need to hook these up to my stock NPP with Green cats. I think there are two options to do this: One to connect right after the cats to the exhaust or full pipes back to the stock muffler and taking out the crushed pipes.



I can't for the life of me figure out who has what I need to do either of those options(with all the clamps etc), without buying the header with it. But I do want the green cats.



Any help would be appreciated. Thanks.

[RobZL1]

I have a set of new green cats for sale if you need them to fab into something custom:

https://www.camaro6.com/forums/showthread.php?t=610124

[Z OH 6]

Originally Posted by BunnyBoy

Have a 2017 ZL1. Recently obtained Kooks 1 7/8 coated headers ONLY for a really good price(No off road X, or Cats).



I'm trying to understand what I need to hook these up to my stock NPP with Green cats. I think there are two options to do this: One to connect right after the cats to the exhaust or full pipes back to the stock muffler and taking out the crushed pipes.



I can't for the life of me figure out who has what I need to do either of those options(with all the clamps etc), without buying the header with it. But I do want the green cats.



Any help would be appreciated. Thanks.

Call Kooks, they have excellent tech support.

[BunnyBoy]

Originally Posted by Z OH 6

Call Kooks, they have excellent tech support.

I emailed them weeks ago but no response. I’ll try calling

[Z OH 6]

Originally Posted by BunnyBoy

I emailed them weeks ago but no response. I’ll try calling

I have talked to Kooks through Email and by phone. Never had an issue with them getting back to me.

[L78toLT1]

You need Kooks part no. 2260330 connection pipes.

[Z OH 6]

Originally Posted by L78toLT1

You need Kooks part no. 2260330 connection pipes.

Correct, and I just sold a set of barely used set of Kooks green cat connection pipes a few days ago on this forum.

[L78toLT1]

Originally Posted by Z OH 6

Correct, and I just sold a set of barely used set of Kooks green cat connection pipes a few days ago on this forum.

Yes you did, and if they had been the new HO green cats, I'd have bought them!

[SHE'Z 18]

Originally Posted by L78toLT1

Yes you did, and if they had been the new HO green cats, I'd have bought them!

See the post by Rob (above). He has a new set that may still be available. He’s a straight shooter.

[Z OH 6]

Originally Posted by L78toLT1

Yes you did, and if they had been the new HO green cats, I'd have bought them!

If they had been the HO cats, they would have been significantly more expensive too but I understand, it all comes down to how much power you expect to make. As long as you keep the car at or below 700-750whp, the standard green cats should be sufficient and if they were to fail for any reason below that level, Kooks would warranty them through GESI.

[L78toLT1]

Originally Posted by Z OH 6

If they had been the HO cats, they would have been significantly more expensive too but I understand, it all comes down to how much power you expect to make. As long as you keep the car at or below 700-750whp, the standard green cats should be sufficient and if they were to fail for any reason below that level, Kooks would warranty them through GESI.

I'm right in the 700 - 750whp ballpark. I generally do a half dozen or more track days per year, often on high speed tracks. I don't think I could go over one season on standard green cats. I'm either going to bite the bullet for some gen2 cats, or just swap on some off road connection pipes for track days. I need to discuss with my tuner (Ted J) to see if I would need a separate, no cat tune for the track.
Going catless on the track is not without complications either. Even with cats, I'm over the decibel limit at a couple of tracks. I have some slip in baffles that I picked up at Camarofest. These get me to just barely within the limits at NCM or AMP. Without cats, I doubt if they would do the trick.

[SHE'Z 18]

L78,
My build will result in nearly the same HP numbers that you’re seeing as well. I’ve searched high and low for an applicable solution to having cats on the Z, even though it’s not required where I live. Im more focused on the fuel odor benefits and the sound suppression that they offer. As I’m planning the addition of 2” headers along with other mods, I’m NOT interested in an obnoxiously loud car. Every video that I’ve heard (including a couple vehicles in person) resulted in a MUCH louder exhaust once the headers were installed. As someone that already has the AWE cat back + PLP’s (secondary cat delete), the sound volume already took a huge jump/improvement. From everything that I’ve researched, it seems like “headers + cats + inline mufflers/resonators” seem to produce a great / manageable exhaust sound. Of course that means the cost goes up and up. Ughhhh

[L78toLT1]

Originally Posted by SHE'Z 18

L78,
My build will result in nearly the same HP numbers that you’re seeing as well. I’ve searched high and low for an applicable solution to having cats on the Z, even though it’s not required where I live. Im more focused on the fuel odor benefits and the sound suppression that they offer. As I’m planning the addition of 2” headers along with other mods, I’m NOT interested in an obnoxiously loud car. Every video that I’ve heard (including a couple vehicles in person) resulted in a MUCH louder exhaust once the headers were installed. As someone that already has the AWE cat back + PLP’s (secondary cat delete), the sound volume already took a huge jump/improvement. From everything that I’ve researched, it seems like “headers + cats + inline mufflers/resonators” seem to produce a great / manageable exhaust sound. Of course that means the cost goes up and up. Ughhhh

Catted headers into the stock npp exhaust sounds very good in my opinion. It's not at all obnoxious at idle or lower rpm. Just cruising down the highway at 70 - 80mph, it's not noticeably different from stock. Many folks have complimented my car's exhaust note at idle.
We don't have emissions inspections in my area, but I have yet to hear a cattless gen6 Camaro with anything approaching a pleasant exhaust tone. It really sucks that it costs a King's ransom for cats that will live at our power levels

[SHE'Z 18]

Yes sir… and at our WHP level, it looks like G-Sport GESI Gen II (850 HP/Bank) is the only way to go.