Are these cats good?

SammYyYyY · 02-12-2024, 01:33 AM

(Apologies for the double post; I wasn't having much luck in the general section and thought I'd post here since it's a ZL1. Mods, please remove if this is not allowed. Thanks!)

Hey all!

I’ve been on the hunt for some Kooks green cats for when I install my headers on my 2018 ZL1 1LE soon; I initially bought a set of headers with high flow catted connection pipes, and was told these will not work under boosted applications due to the ceramic substrate melting.

I found some green catted connection pipes for a reasonable price from a really nice gentleman in another state; I think they look good, but before I pull the trigger and have them shipped over I wanted to ask and make sure they look good to everyone else. The only concern I have with them is some very slight bending in the substrate in picture 3, but I’ve been told this is pretty normal.

For what it is worth, my build is going to be very light for now; just headers/exhaust, intake, and maybe a throttle body (I say maybe because I might hold off on this until I port the blower next year so I can fit a 103mm rather than buying a 95mm now that will be a bottleneck with a ported blower). Just shooting for ~600 WHP for now. Let me know what y’all think. Thanks all!

Name: cat1.jpg
Views: 241
Size: 84.2 KB

*radz28* · 02-12-2024, 07:01 AM

I wouldn't pay to put them on my car. They look like they're already coming apart. They look kinda' small, too.

SammYyYyY · 02-12-2024, 09:58 AM

Quote:

Originally Posted by radz28

I wouldn't pay to put them on my car. They look like they're already coming apart. They look kinda' small, too.

Fair enough; I wasn’t so much concerned about the size as they are the Kooks Green cats, moreso about if that slight substrate bending was normal. That’s totally fair!

Joshinator99 · 02-12-2024, 12:48 PM

Quote:

Originally Posted by SammYyYyY

Fair enough; I wasn’t so much concerned about the size as they are the Kooks Green cats, moreso about if that slight substrate bending was normal. That’s totally fair!

You need GESI Gen2 cats if you want them to stand up to boosted power. I believe Kooks might now be using them in the Green Cats as well but you’ll have to check. The original Green Cats did not hold up.

SammYyYyY · 02-12-2024, 01:49 PM

Quote:

Originally Posted by Joshinator99

You need GESI Gen2 cats if you want them to stand up to boosted power. I believe Kooks might now be using them in the Green Cats as well but you’ll have to check. The original Green Cats did not hold up.

Gotcha. Yeah, I thought I read somewhere that Kooks switched to GESi gen 2s for their green cats a little while back. The owner says these were bought directly from Kooks less than a year ago.

Joshinator99 · 02-12-2024, 05:11 PM

Quote:

Originally Posted by SammYyYyY

Gotcha. Yeah, I thought I read somewhere that Kooks switched to GESi gen 2s for their green cats a little while back. The owner says these were bought directly from Kooks less than a year ago.

Doesn’t matter as they still offer two versions. You need the HO Green Cats it looks like.

TLDR; if they’re cheap, they’re not the ones you want lol.
https://kooksheaders.com/components/...-converter1702

Z OH 6 · 02-12-2024, 06:10 PM

Quote:

Originally Posted by SammYyYyY

Gotcha. Yeah, I thought I read somewhere that Kooks switched to GESi gen 2s for their green cats a little while back. The owner says these were bought directly from Kooks less than a year ago.

Kooks labels all of their cats as "Green Cats", but as Josh stated, you want the HO Green Cats. They withstand a LOT more power than the original Green Cats. Those were only good to around 700whp but some people started seeing the same thing you're seeing at that power level, myself included.

Laidoffsick · 02-14-2024, 09:37 AM

Get the Ultra cats from Complete Street Performance

Joshinator99 · 02-14-2024, 11:13 AM

Quote:

Originally Posted by Laidoffsick

Get the Ultra cats from Complete Street Performance

Same thing as HO Green Cats lol. All made by GESI.

bertie · 02-14-2024, 07:14 PM

Quote:

Originally Posted by Joshinator99

Same thing as HO Green Cats lol. All made by GESI.

No wonder are they both quality cats.

Joshinator99 · 02-14-2024, 08:34 PM

Quote:

Originally Posted by bertie

No wonder are they both quality cats.

As stated above, if you’re boosted you want the GESI GEN2 only (also used by Kooks and CSP under different names). Confirm that’s what you’re getting before placing the order and all will be well.

dfxrte · 02-14-2024, 09:33 PM

no cats are good

02-12-2024, 01:33 AM	#1
SammYyYyY Drives: 2018 ZL1 1LE Join Date: May 2022 Location: Salt Lake City Posts: 83	Are these cats good? (Apologies for the double post; I wasn't having much luck in the general section and thought I'd post here since it's a ZL1. Mods, please remove if this is not allowed. Thanks!) Hey all! I’ve been on the hunt for some Kooks green cats for when I install my headers on my 2018 ZL1 1LE soon; I initially bought a set of headers with high flow catted connection pipes, and was told these will not work under boosted applications due to the ceramic substrate melting. I found some green catted connection pipes for a reasonable price from a really nice gentleman in another state; I think they look good, but before I pull the trigger and have them shipped over I wanted to ask and make sure they look good to everyone else. The only concern I have with them is some very slight bending in the substrate in picture 3, but I’ve been told this is pretty normal. For what it is worth, my build is going to be very light for now; just headers/exhaust, intake, and maybe a throttle body (I say maybe because I might hold off on this until I port the blower next year so I can fit a 103mm rather than buying a 95mm now that will be a bottleneck with a ported blower). Just shooting for ~600 WHP for now. Let me know what y’all think. Thanks all!

02-12-2024, 07:01 AM	#2
radz28 Petro-sexual Drives: Ultra-Grin Join Date: Oct 2006 Location: Crazy Coast Posts: 15,201 View My Garage	I wouldn't pay to put them on my car. They look like they're already coming apart. They look kinda' small, too. __________________ '20 ZL1 Black "Fury" A10, PDR, Exposed CF Extractor Magnuson Magnum DI TVS2650R // RFBG // Soler 103 // TooHighPSI Port Injection // THPSI Billet Lid // FF // Katech Drop-In // PLM Heat Exchanger // ZLE Cradle bushings // BMR Chassis-Suspension Stuff // aFe Bars // Diode Dynamics LEDs // ACS Composites Guards // CF Dash // Aeroforce // tint // other stuffs

02-14-2024, 09:37 AM	#8
Laidoffsick Drives: Camaro ZL1 Join Date: Apr 2023 Location: Albuquerque, NM Posts: 17	Get the Ultra cats from Complete Street Performance __________________ 2022 ZL1 Red Hot. Mods: OEM 1LE 19" wheels, PS4S tires 325/305, LED side markers, Rock Guards, 2" CSP Longtube Headers (made by Kooks), Catless, Rotofab Big Gulp, DSX Flex Fuel, Soler Performance LT5 ported throttle body w/ adapter plate, MSD Plug wires, LSA SC Reservoir upgrade, Custom tune, E54 w/91 Octane, 677 rwhp, 714 ft/lb.

02-14-2024, 09:33 PM	#12
dfxrte Drives: 22 ZL1 M6 Join Date: Oct 2018 Location: GTA Posts: 345	no cats are good __________________ Sold: '17 m6 2SS [arctic blue] Current: '22 m6 zl1 [vivid orange]

User Name		Remember Me?
Password