Catless down pipes - SMELL
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AMG GTS
Catless down pipes - SMELL
Has any one installed catless downpipes? Do you get fuel smell and how bad is it?
I’m Interetsed in getting more sound from the exhaust.
Research is telling me to get catless downpipes and tune.
only concern is the smell in the cabin
I’m Interetsed in getting more sound from the exhaust.
Research is telling me to get catless downpipes and tune.
only concern is the smell in the cabin
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Start here imo, cheap and reversible:
https://mbworld.org/forums/amg-gt/73...dary-cats.html
https://mbworld.org/forums/amg-gt/67...at-delete.html
https://mbworld.org/forums/amg-gt/73...dary-cats.html
https://mbworld.org/forums/amg-gt/67...at-delete.html
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Patana-to answer your question, yes, you will get a fuel type smell.
How much/how bad, depends on you. People that love that race car / being at the race track smell, will either love it or not notice at all. Someone that’s never been around it will absolutely notice.
All this pertains to outside the car, not inside.
Now you also say “more sound”, you do not say you are seeking better performance.
Catless downpipes make the turbos spool faster since eliminating back pressure, add 15hp at wheels, and increase mid range torque as well as top end flow.
Remember, for performance, catless downpipes are the only solution which eliminate the big restrictive catalysts off the back side of turbo housing on the downpipe.
How much/how bad, depends on you. People that love that race car / being at the race track smell, will either love it or not notice at all. Someone that’s never been around it will absolutely notice.
All this pertains to outside the car, not inside.
Now you also say “more sound”, you do not say you are seeking better performance.
Catless downpipes make the turbos spool faster since eliminating back pressure, add 15hp at wheels, and increase mid range torque as well as top end flow.
Remember, for performance, catless downpipes are the only solution which eliminate the big restrictive catalysts off the back side of turbo housing on the downpipe.
Last edited by dlefty; Jan 17, 2020 at 09:39 AM.
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Faster spool is just a fact that cannot be debated. Less back pressure equals faster spool from the turbo.
As far as power, I can draw a line on a graph no problem
Seriously though, on power, that’s where most turbo cars fall give or take 1-3HP. Daytona Turbos, Talons, Eclipses, 3000GT, Supra, 300ZX, Nissan GTR, AMG GT Platform are the ones that come to mind I’ve worked on.
As far as power, I can draw a line on a graph no problem
Seriously though, on power, that’s where most turbo cars fall give or take 1-3HP. Daytona Turbos, Talons, Eclipses, 3000GT, Supra, 300ZX, Nissan GTR, AMG GT Platform are the ones that come to mind I’ve worked on.
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Faster spool is just a fact that cannot be debated. Less back pressure equals faster spool from the turbo.
As far as power, I can draw a line on a graph no problem
Seriously though, on power, that’s where most turbo cars fall give or take 1-3HP. Daytona Turbos, Talons, Eclipses, 3000GT, Supra, 300ZX, Nissan GTR, AMG GT Platform are the ones that come to mind I’ve worked on.
As far as power, I can draw a line on a graph no problem
Seriously though, on power, that’s where most turbo cars fall give or take 1-3HP. Daytona Turbos, Talons, Eclipses, 3000GT, Supra, 300ZX, Nissan GTR, AMG GT Platform are the ones that come to mind I’ve worked on.
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OP should also be aware that there is a very large cost in installing these pipes. First of all the pipes themselves are ridiculously expensive for a pipe lol. Then you have the specter of optional high-speed cats which are very expensive so you won’t throw a CEL. secondly, I believe you have to lift the engine off the engine mounts to install? Which becomes a ridiculously expensive Enterprise for a little more noise and 10 hp to the wheels.
As everyone has said over and over again try removing the secondary cats and if you’re happy Call it a day.
As everyone has said over and over again try removing the secondary cats and if you’re happy Call it a day.
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OP should also be aware that there is a very large cost in installing these pipes. First of all the pipes themselves are ridiculously expensive for a pipe lol. Then you have the specter of optional high-speed cats which are very expensive so you won’t throw a CEL. secondly, I believe you have to lift the engine off the engine mounts to install? Which becomes a ridiculously expensive Enterprise for a little more noise and 10 hp to the wheels.
As everyone has said over and over again try removing the secondary cats and if you’re happy Call it a day.
As everyone has said over and over again try removing the secondary cats and if you’re happy Call it a day.
The removal of the factory 1 piece downpipes is not as simple. The stock downpipes are bulky and cannot come out as easily as putting the new pipes in. To remove the stock downpipes, you must drop the center driveline tunnel working from both the bottom and top to undo necessary bolts, clamps, and lines. We recommend a qualified and experienced shop to perform this service.
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OP should also be aware that there is a very large cost in installing these pipes. First of all the pipes themselves are ridiculously expensive for a pipe lol. Then you have the specter of optional high-speed cats which are very expensive so you won’t throw a CEL. secondly, I believe you have to lift the engine off the engine mounts to install? Which becomes a ridiculously expensive Enterprise for a little more noise and 10 hp to the wheels.
As everyone has said over and over again try removing the secondary cats and if you’re happy Call it a day.
As everyone has said over and over again try removing the secondary cats and if you’re happy Call it a day.
As far as the labor cost to install. You CAN get everything out in 1-piece by dropping down driveshaft. It will cost you if paying someone else.
BUT, if you have, or know someone that has a LITTLE bit of welding and fab skill, this is the easiest, here’s an example of what someone
did when helping a fellow GT owner in your same situation. Since aftermarket downpipes are 2-pc. super easy install, we created the stock downpipes in this same 2-pc super easy install situation so it is super easy to put in and out of the car. Best part is you do NOT have to drop or remove anything of any consequence like the driveshaft when doing it this way.....so minimal labor involved.And as you can see, why I always harp on downpipes, by going aftermarket, you eliminate that tight bend restrictive catalyst off the back side of turbo housing, which is something you only accomplish by doing aftermarket downpipes.
Factory converted to 2pc
Aftermarket
Last edited by dlefty; Jan 17, 2020 at 11:19 AM.
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BUT, if you have, or know someone that has a LITTLE bit of welding and fab skill, this is the easiest, here’s an example of what someone
did when helping a fellow GT owner in your same situation. Since aftermarket downpipes are 2-pc. super easy install, we created the stock downpipes in this same 2-pc super easy install situation so it is super easy to put in and out of the car. Best part is you do NOT have to drop or remove anything of any consequence like the driveshaft when doing it this way.....so minimal labor involved.Factory converted to 2pc
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Um yes.....this is not the what set you off terminology “half a$$” cut out secondary cats for sound increase.
This is converting your factory downpipes to 2-pieces and leaving them operate as normal with the added benefit of you having the same set up as aftermarket downpipes for quick and COMPLETE removal and installation. THIS IS NOT a performance enhancement, it’s an ease of back and forth modification for those, ready to be upset.....that want to do it right FROM A PERFORMANCE perspective and eliminate as much back pressure and restriction as possible....go
aftermarket downpipes.....with quick ability to change back and forth without dropping g drive shaft.
You confuse me behind your keyboard with jumping in every time someone makes a suggestion that isn’t your way of doing it. Man, Must be miserable to live that life.
Lets just clutter up another thread of someone’s with a bunch of crap! Yeah!
And your favorite word is CHEAP, we get it, you’re cheap!
This is converting your factory downpipes to 2-pieces and leaving them operate as normal with the added benefit of you having the same set up as aftermarket downpipes for quick and COMPLETE removal and installation. THIS IS NOT a performance enhancement, it’s an ease of back and forth modification for those, ready to be upset.....that want to do it right FROM A PERFORMANCE perspective and eliminate as much back pressure and restriction as possible....go
aftermarket downpipes.....with quick ability to change back and forth without dropping g drive shaft.
You confuse me behind your keyboard with jumping in every time someone makes a suggestion that isn’t your way of doing it. Man, Must be miserable to live that life.
Lets just clutter up another thread of someone’s with a bunch of crap! Yeah!
And your favorite word is CHEAP, we get it, you’re cheap!
Last edited by dlefty; Jan 17, 2020 at 11:55 AM.
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I think @dlefty has correct information.
I’ve had catless DPs and tune for four years. IIRC my car dynoed 56x whp instead of ~545whp like most tuned cars according to Eurocharged Houston. Also picked up a decent amount of midrange torque. I think Weistec has dyno graphs on their website between their W1 and W2 package which is the same thing.
I’ve done tune vs down pipes and tune on several cars now. Even though they don’t pick up much peak hp, you will notice a clear difference in how fast the turbos spool/respond. In a race, I doubt they’re worth more than 1mph trap or 1 car length on the highway (if that). Not a must have mod but you can definitely feel the difference driving around.
I’ve also had friends behind me say they can hear the turbos spooling when I haul ***. I can’t tell from inside the cabin tbh.
The car will smell if you're standing behind it. It won't smell from inside the cabin except maybe if you're stuck at a red light with your windows down for some time.
If you are willing to cut your stock down pipes, the install is quick and painless. If you want to keep your stock DPs in tact, it is not worth the headache. You have to drop the entire subframe. I had my DPs done locally for less than half what the retailers charge. The Euro car tax on these products is remarkable. I could get full headers and exhaust for my Corvette stuff for the same price as what they charge for these tiny downpipes.
I’ve had catless DPs and tune for four years. IIRC my car dynoed 56x whp instead of ~545whp like most tuned cars according to Eurocharged Houston. Also picked up a decent amount of midrange torque. I think Weistec has dyno graphs on their website between their W1 and W2 package which is the same thing.
I’ve done tune vs down pipes and tune on several cars now. Even though they don’t pick up much peak hp, you will notice a clear difference in how fast the turbos spool/respond. In a race, I doubt they’re worth more than 1mph trap or 1 car length on the highway (if that). Not a must have mod but you can definitely feel the difference driving around.
I’ve also had friends behind me say they can hear the turbos spooling when I haul ***. I can’t tell from inside the cabin tbh.
The car will smell if you're standing behind it. It won't smell from inside the cabin except maybe if you're stuck at a red light with your windows down for some time.
If you are willing to cut your stock down pipes, the install is quick and painless. If you want to keep your stock DPs in tact, it is not worth the headache. You have to drop the entire subframe. I had my DPs done locally for less than half what the retailers charge. The Euro car tax on these products is remarkable. I could get full headers and exhaust for my Corvette stuff for the same price as what they charge for these tiny downpipes.
Last edited by kumizi; Jan 17, 2020 at 01:32 PM.
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I think @dlefty has correct information.
I’ve had catless DPs and tune for four years. IIRC my car dynoed 56x whp instead of ~545whp like most tuned cars according to Eurocharged Houston. Also picked up a decent amount of midrange torque. I think Weistec has dyno graphs on their website between their W1 and W2 package which is the same thing.
I’ve done tune vs down pipes and tune on several cars now. Even though they don’t pick up much peak hp, you will notice a clear difference in how fast the turbos spool/respond. In a race, I doubt they’re worth more than 1mph trap or 1 car length on the highway (if that). Not a must have mod but you can definitely feel the difference driving around.
I’ve also had friends behind me say they can hear the turbos spooling when I haul ***. I can’t tell from inside the cabin tbh.
The car will smell if you're standing behind it. It won't smell from inside the cabin except maybe if you're stuck at a red light with your windows down for some time.
If you are willing to cut your stock down pipes, the install is quick and painless. If you want to keep your stock DPs in tact, it is not worth the headache. You have to drop the entire subframe. I had my DPs done locally for less than half what the retailers charge. The Euro car tax on these products is remarkable. I could get full headers and exhaust for my Corvette stuff for the same price as what they charge for these tiny downpipes.
I’ve had catless DPs and tune for four years. IIRC my car dynoed 56x whp instead of ~545whp like most tuned cars according to Eurocharged Houston. Also picked up a decent amount of midrange torque. I think Weistec has dyno graphs on their website between their W1 and W2 package which is the same thing.
I’ve done tune vs down pipes and tune on several cars now. Even though they don’t pick up much peak hp, you will notice a clear difference in how fast the turbos spool/respond. In a race, I doubt they’re worth more than 1mph trap or 1 car length on the highway (if that). Not a must have mod but you can definitely feel the difference driving around.
I’ve also had friends behind me say they can hear the turbos spooling when I haul ***. I can’t tell from inside the cabin tbh.
The car will smell if you're standing behind it. It won't smell from inside the cabin except maybe if you're stuck at a red light with your windows down for some time.
If you are willing to cut your stock down pipes, the install is quick and painless. If you want to keep your stock DPs in tact, it is not worth the headache. You have to drop the entire subframe. I had my DPs done locally for less than half what the retailers charge. The Euro car tax on these products is remarkable. I could get full headers and exhaust for my Corvette stuff for the same price as what they charge for these tiny downpipes.
Good info, but I'd need to see some independent/customer dyno sheets to believe the 15whp claim from just DP. Especially when Weistec claims +192hp/+287tq at the crank, from just their DPs.
https://www.weistec.com/amg-gt-downpipes.html
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I had an Audi S3 for a little while. It only picked up 7-8whp with DPs but the turbos would spool like 400RPM quicker.
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Might be a dumb question but, When you do the catless downpipes, are you also doing the midpipes to get rid of the secondary cats? What is the best set up for this? Anyone running downpipes and secondary delete and res delete?
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For this platform, Catless downpipes eliminate all 4 catalysts on the vehicle.
