APEX GT3

Anyone with experience running a HJS Sport Cat that has also driven or heard a car with a Cat Bypass?

Is it just a matter of the smell with the bypass since the sport cats have about 90% less restrictions in the stock anyways?

Big sound difference between both?
Power difference?

If you are doing an ECU tune, there isn’t a concern with the check engine light on either option.

Trying to make a decision this week on going sport cat or bypass. Keeping the PSE exhaust and doing a tune to open the valves.

Thanks for any input!

reddsektor

I have fabspeed cat bypass on mine with PSE, a local friend has soul sport cats + exhaust on his. The sound is different because of the exhausts, but loudness is about the same.

Cat bypass itself will be just slightly louder than sport cats, but it may be hard to notice the difference.

Power wise, bypass will give about 5 more hp (+20 with sport cats and +25 with bypass are the the average numbers).

I went with bypass and my M-Eng stage2 tune (deletes the CEL) because here in Texas it’s easy to pass emissions with my local guy, and I wanted the most amount of sound/power possible with PSE… plus the bypass is about $1600 cheaper lol

Tupper

The advantage with sport cats is lack of smell and, if you don’t get a CEL it’s smooth sailing with emissions testing.

smartbot

I have the Fabspeed Sport Cats and they work great. I haven't had any issues with the check engine light and it sounds louder (with the stock PSE)! I would save yourself the trouble and just get the Sport Cats... Here is a quick clip:

APEX GT3

What year is your car?

smartbot

It's a 2020 Carrera S

APEX GT3

Thanks! There is some talk on these forums about the 2021/2022 having a more sensitive ECU for the airflow and emissions system. I have a 2021 Base. A bit more sensitive to the high flow cats... big mystery!

Andy2021

I own a 2021 Carrera S and after waiting about 8 weeks, just received and installed the Fabspeed sport cats. I’m very happy with them. Super easy to install. I don’t have PSE intentionally, because preferred to go after-market for the exhaust system. In the meantime, I wanted to hear how it sounded with the sport cats only, before deciding to purchase the Fabspeed exhaust.

I decided to purchase the Fabspeed exhaust too and after speaking with a sales rep at Fabspeed today, he explained that because my Porsche doesn’t have PSE, it doesn’t have the PSE button that controls the valves to open/close. He said I could still install the exhaust. He said all I have to do is switch the valve controllers/motors from the stock exhaust to the new exhaust before installing the exhaust in the car.

Then he said I will have to take it to the dealership, where they can program the PCM for PSE. He said doing so will also create a feature in the PCM display that will allow me to control the exhaust valves.

I called my dealership and spoke with my svc rep and explained the above. He called me back after speaking with a Porsche mechanic and said they can do it, but it would cost anywhere from $450 to $1,200 depending on what issues my arise in the process.

Does this sound correct? Thank you.

AlterZgo

@992StormTrooper - I don't have any experience w/ running a cat bypass on a 992, but I have done this on a white car I had in the past. Aside from the smell, the tainted exhaust fumes stained by white bumper pretty regularly. This was more than 20 yrs ago and cars back then polluted a lot more than today. Perhaps a decatted 992 would run clean enough to avoid this issue, but something else to consider since your car is white.

mksz51

Bypass = illegal = "F-You Mother Nature". Some people actually care about stuff like that.

Richard_Wallace

I had the PSE function enabled on my non-PSE 2022 Targa 4S. They did it when my car arrived at the dealer during the pre-delivery prep. They initially told me it would be 100 dollars to do it (I provided the instructions on how to do it - see other threads on this topic). It literally took them 10 minutes and they ended up not charging me - and they thought it was cool - and for those without PSE they thought it was a good option.) It now works just like my previous 992 C4S with PSE. The toggle switch now opens and closes the valves and when in sport/sport+ it automatically turns it on - also shows the check box in the PCM as well - so exactly like it was optioned with PSE.

The price quote they gave you is way high - it should take them literally 10 minutes to do (from what my SA told me). so should be no more than 1 hour labor IMO.

PS. The sound difference between my previous 992 with PSE and my new Targa without PSE (but enabled) is about 80% as loud. So for free having this done, was pretty nice upgrade - and I get to have my quad exhausts!

shrimp money

Yeah, like the people that build mansions on the beach and fly privately.

centaur

Lack of that horrible smell is a HUGE advantage with the sport catalytics. I always crack up when I see some tool show up at a cars and coffee with a McClaren or the like uncatted and it smells like a 50 year old school bus. Redneck stuff for sure.

centaur

Yeah really. The earth will stop rotating because some guy has a bypass on his catalytics. Hilarious.
Does spitting in the ocean ring a bell?
These save the earth drum beaters might want to direct their negativity towards China and India if reality has a place in their mission.

mksz51

And you wonder why there's a common stereotype of Porsche owners being arrogant and generally "above it all". You must not have children, grandchildren or any care for the future we're giving to the rest of the world. My condolences.