Help Kooks Headers vs Corsa CB Exhaust

[blkout]

If anyone has ARH headers, would love the feedback. It was Kooks only for so long, but we finally have choices.

ARH are fantastic, they have always been top quality.

 

[Jfkayne]

I have a thread here about my exhaust mods. I replaced factory mufflers with aftermarket pass-through mufflers. Re-used factory tips. Local shop custom made all the mods for under $750. It sounds much better, but still not enough for me.

Its noticeably louder than stock with the flaps open. But still quiet enough that you don't notice it while maintaining conversation with your passenger. The flaps still quiet it down if necessary, but I never find it to be so.

Unfortunately, the shop nor I knew about the procedure to re-link the ECU with the muffler flaps, so I did get a CEL even though I changed nothing related to cats or upstream from the mufflers.

I don't understand why y'all are even considering keeping stock mufflers with headers though. It defeats the whole point of headers to keep stock mufflers.

My warranty is up next Spring, so I plan to add the Kooks and get it tuned anyway. I figure the flaps will keep it contained enough if I ever need to. The tune is ridiculously expensive, but there are few conveniences I just want to have....and killing the CEL will be nice. Ironically, the CEL is hidden behind my steering wheel, so I forget about it.

Can't wait to fire it up after that

Not sure I understand regarding the CB exhaust. Many factory exhausts are made really well and sound great. Changing the CB exhaust often adds minimal power gains and often little exhaust note differences. IE my other car is an F12. If you swap out the exhaust it does next to nothing and it will cost you $10k. Swap the 800 cel cats for race/green cats, with the factory exhaust, and it’s a completely different ballgame. It fucking screams. Best upgrade by far.

In all honesty from the videos I have seen I really don’t hear that much of a difference going from factory exhaust to Corsa Extreme but that might just be the videos. That is why I was thinking about going the same route as my F12 (green cats and factory CB). If anyone lives around the Westchester, NY area and has a Corsa installed I would love to meet-up for a listen.

 

[Ryana1992]

ARH are fantastic, they have always been top quality.

Any issues with CEL?

 

[Ryana1992]

A

I just installed the Corsa cat back exhaust on my 2026 5BW yesterday. I cant recommend it enough. Huge sound improvements. Much louder but nice and deep with no rasp and no drone. I have a friend who is planning to install Kooks headers while keeping stock exhaust. I’ll do a sound comparison as soon as he does it.

Any update on this? Comparing these two?

 

[blkout]

Any issues with CEL?

I am not using headers at this time. I have a Corsa catback with the stock manifolds and stock cats.

 

[Ryana1992]

I just ordered kooks headers with green cats and am planning to use the factory exhaust and retain oem tips for a 5BW. Will see how it sounds.

Any update?

 

[Ryana1992]

I am not using headers at this time. I have a Corsa catback with the stock manifolds and stock cats.

Ah ok, ARH uses 300 cell cats with 400 cell optional, was curious if the 300 cell will cause a CEL. Also not sure what cell Kooks is using in their green cats.

 

[marcmac]

Ah ok, ARH uses 300 cell cats with 400 cell optional, was curious if the 300 cell will cause a CEL. Also not sure what cell Kooks is using in their green cats.

I think ARH, Stainless works and Kooks are using the Gesi green cats on the 5BW, the latter 2 definitely use the gesi cats. the 3rd Gen CTSvs use different cats on there longtubes sets

 

[Kawman]

Yes, ARH uses G-Sport cats, but it's not as simple as that. G-Sport has cats that range in price form $100 to $1,200, so you really need to know exactly which cat is being offered to do a proper comparison. Here's a general rule of thumb:

200 cell cats - you're going to have CEL issues
300 cell cats - you're likely going to have CEL issues
400 cell cats - you're likely not going to have CEL issues

And with a 400 cell cats, is it a 2.5", 3" or 4" inlet? Is the body OD 4", 4.5", 5", or 6"? What hp level are they rated for?

What hasn't been mentioned is using a high flow 2-stage cats. Your OEM housing has first an 800 cell cat, an air gap where a sensor takes a reading and then a 200 cell cat. Ya'll are doing 200, 300 or 400 cell cats, but I would do a G-Sport 400/200 2-stage cat, with a 3" inlet and 5" body rated for 1,000hp. Spend a few extra bucks and get the absolute best part for the job.

 

[Jfkayne]

Yes, ARH uses G-Sport cats, but it's not as simple as that. G-Sport has cats that range in price form $100 to $1,200, so you really need to know exactly which cat is being offered to do a proper comparison. Here's a general rule of thumb:

200 cell cats - you're going to have CEL issues
300 cell cats - you're likely going to have CEL issues
400 cell cats - you're likely not going to have CEL issues

And with a 400 cell cats, is it a 2.5", 3" or 4" inlet? Is the body OD 4", 4.5", 5", or 6"? What hp level are they rated for?

What hasn't been mentioned is using a high flow 2-stage cats. Your OEM housing has first an 800 cell cat, an air gap where a sensor takes a reading and then a 200 cell cat. Ya'll are doing 200, 300 or 400 cell cats, but I would do a G-Sport 400/200 2-stage cat, with a 3" inlet and 5" body rated for 1,000hp. Spend a few extra bucks and get the absolute best part for the job.

Is there a manufacturer that offers this or something you need to have made?