991.2 Cat Bypass owners
#16
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Join Date: Mar 2017
Location: Philadelphia, Pennsylvania
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Hello All,
My name is Phil and I am reaching out from Fabspeed.
This is a very sticky topic for owners everywhere. There are huge upsides to both and downsides to both.
Pro's
Sport Cat's:
1. No check engine light
2. Low fuel smell
3. great sound
4. 93% Free flow when using HJS High flow catalytic converters
Con's
1.Price much more expensive of Cat bypass
2. Leaves some power on the table
Cat bypass
Pro's
1. Raw sound
2 100% free flow
3. The most power you will be able to get out of the part
Con's
1. Smell
2. Check engine light
3. Issues with emissions in some states
If it is not a track only car we highly suggest going with the sport cats. It is less of a headache for emissions, CEL, and smell. Also if you are going with cat bypass normally you will go with a performance muffler or no muffler. If it is a track only car to get the real benefits of the Cat bypass you should go with the full exhaust and you might end up with going over DB ratings at some tracks. We do make some turn down tips to help out with sound but now you are fighting sound as well.
I hope this helps
My name is Phil and I am reaching out from Fabspeed.
This is a very sticky topic for owners everywhere. There are huge upsides to both and downsides to both.
Pro's
Sport Cat's:
1. No check engine light
2. Low fuel smell
3. great sound
4. 93% Free flow when using HJS High flow catalytic converters
Con's
1.Price much more expensive of Cat bypass
2. Leaves some power on the table
Cat bypass
Pro's
1. Raw sound
2 100% free flow
3. The most power you will be able to get out of the part
Con's
1. Smell
2. Check engine light
3. Issues with emissions in some states
If it is not a track only car we highly suggest going with the sport cats. It is less of a headache for emissions, CEL, and smell. Also if you are going with cat bypass normally you will go with a performance muffler or no muffler. If it is a track only car to get the real benefits of the Cat bypass you should go with the full exhaust and you might end up with going over DB ratings at some tracks. We do make some turn down tips to help out with sound but now you are fighting sound as well.
I hope this helps
#17
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Join Date: Jan 2016
Location: Where aspirations are natural
Posts: 4,389
Likes: 0
Received 42 Likes
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33 Posts
Hello All,
My name is Phil and I am reaching out from Fabspeed.
This is a very sticky topic for owners everywhere. There are huge upsides to both and downsides to both.
Pro's
Sport Cat's:
1. No check engine light
2. Low fuel smell
3. great sound
4. 93% Free flow when using HJS High flow catalytic converters
Con's
1.Price much more expensive of Cat bypass
2. Leaves some power on the table
Cat bypass
Pro's
1. Raw sound
2 100% free flow
3. The most power you will be able to get out of the part
Con's
1. Smell
2. Check engine light
3. Issues with emissions in some states
If it is not a track only car we highly suggest going with the sport cats. It is less of a headache for emissions, CEL, and smell. Also if you are going with cat bypass normally you will go with a performance muffler or no muffler. If it is a track only car to get the real benefits of the Cat bypass you should go with the full exhaust and you might end up with going over DB ratings at some tracks. We do make some turn down tips to help out with sound but now you are fighting sound as well.
I hope this helps
My name is Phil and I am reaching out from Fabspeed.
This is a very sticky topic for owners everywhere. There are huge upsides to both and downsides to both.
Pro's
Sport Cat's:
1. No check engine light
2. Low fuel smell
3. great sound
4. 93% Free flow when using HJS High flow catalytic converters
Con's
1.Price much more expensive of Cat bypass
2. Leaves some power on the table
Cat bypass
Pro's
1. Raw sound
2 100% free flow
3. The most power you will be able to get out of the part
Con's
1. Smell
2. Check engine light
3. Issues with emissions in some states
If it is not a track only car we highly suggest going with the sport cats. It is less of a headache for emissions, CEL, and smell. Also if you are going with cat bypass normally you will go with a performance muffler or no muffler. If it is a track only car to get the real benefits of the Cat bypass you should go with the full exhaust and you might end up with going over DB ratings at some tracks. We do make some turn down tips to help out with sound but now you are fighting sound as well.
I hope this helps
#18
I would say that the smell issue has much more to do with the ecu calibration in whatever front engine car(s) you are referring to. The Porsche may self adjust for the mods much more accurately and keep the a/f ratio in check. Many cars are significantlyricher than optimal in stock form anyway, in an effort to reduce detonatin (pinging). The relative positon of the engine cannot possibly impact the smell any more than the color of the interior in the car would.
#19
Rennlist Member
With PSE turned off, the sound level is acceptable, and my wife and neighbors don't seem to notice. Being an old gearhead who grew up loving cars from the 50s, 60s, and 70s, the smell doesn't bother me. I just want that serious sound! A guess is the turbos spool up a little quicker and might provide a little more power, but have not seen any dyno curves that show this. I'm lovin em!
#20
I have bypass pipes on my S/X51, and the sound is AMAZING with PSE turned On! It sounds more like 5.0 L than 3.0 L. And it's loud when you want it loud. The two distinct turbo whistles in Sport+ mode add unique drama that a naturally aspirated engine does not have.
With PSE turned off, the sound level is acceptable, and my wife and neighbors don't seem to notice. Being an old gearhead who grew up loving cars from the 50s, 60s, and 70s, the smell doesn't bother me. I just want that serious sound! A guess is the turbos spool up a little quicker and might provide a little more power, but have not seen any dyno curves that show this. I'm lovin em!
With PSE turned off, the sound level is acceptable, and my wife and neighbors don't seem to notice. Being an old gearhead who grew up loving cars from the 50s, 60s, and 70s, the smell doesn't bother me. I just want that serious sound! A guess is the turbos spool up a little quicker and might provide a little more power, but have not seen any dyno curves that show this. I'm lovin em!
for that - hearing/reading mixed reviews on this
#21
Rennlist Member
For a car that is not driven daily and/or used for racing cat delete makes sense due to noise and smell. For daily driver in my opinion use sport cats. I have one of each setup and catless DOES smell...worse with tune as it is usually setup to run richer.
#22
Car is not a daily - just a weekend carsNcoffee or back road toy.
#23
Rennlist Member
You can run without a tune but it does not maximize performance benefits. For weekend use and sound you vould live with it but you still would need to deal with the CEL and emissio. Inspection issues.
#24
Its not worth it if the bypass causes problems. Better off with sport cats. But if the bypass does NOT cause any issues - just an occasional light that clears itself thats a different story
#25
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SOUL PERFORMANCE PRODUCTS
Quality Exhaust Solutions, Fair Pricing, and Outstanding Service
John Gaydos- Owner, Performance Specialist
Cell - (484) 883-6197
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Jon Wheel - Marketing Manager
jwheel@soulpp.com
SOUL PERFORMANCE PRODUCTS
Quality Exhaust Solutions, Fair Pricing, and Outstanding Service
John Gaydos- Owner, Performance Specialist
Cell - (484) 883-6197
johng@soulpp.com
Jon Wheel - Marketing Manager
jwheel@soulpp.com
#26
Rennlist Member
My indie has em on his GTS installed like mine, and he says he has had no CEL. But he does have a COBB tune...
For me, the sounds with PSE on are worth the CEL nuisance. Sounds more like 5.0 than 3.0 TT. And it is still reasonably quiet using the muffler, when going past speed cops 🚔👮. 😀
#27
#28
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#29
#30
Rennlist Member
The light is a PIA and will be an issue at some point for resale or when bringing to dealer for service. Best to get it taken care of with O2 spacers or tune to shut off the code from throwing.