Catted Downpipe Help

tobefair-idontcare · 07-02-2018, 06:43 PM

This is a multi question thread for some collective forum help. I am interested in getting an aftermarket down-pipe down the road, however I don't really want to the sound to change from my current setup (MPPSK). I'm looking at purchasing a down-pipe with catalytic converter and my questions are: 1.) By keeping the car catted will my current exhaust sound remain the same? Not to the exact decibel level, but close. 2.) Will the power increase be on par with a catless system? 3.) What's the best down-pipe brand to go with knowing the information from the previous two questions?

Any help would be appreciated. I'm open to advice, suggestions, guidance and recommendations. Thanks, gents!

tobefair-idontcare · 07-03-2018, 01:39 PM

Bump. Any help would be appreciated.

G.Newt · 07-03-2018, 01:58 PM

All aftermarket downpipes will increase sound. They're larger in diameter and the catted ones typically have a less dense (cspi) catalytic converter to allow more flow (sound).

Power isn't much different unless you're trying to push big numbers. But anything aftermarket will perform better than OEM.

B58 · 07-07-2018, 12:29 PM

You will feel a sound difference with a catted down-pipe because the size of the cat is much smaller then the oem and the piping is larger, but it won't be loud like the cat-less. I just ordered a DS1 catted down-pipe and the MPE axle back exhaust so I'm hoping it will be a good combo.

BulsaraF36 · 07-07-2018, 01:00 PM

I have Fabspeed catted dp installed along with MPPK/MPE and Dinan stage 3 when I recorded this video.

tobefair-idontcare · 07-07-2018, 09:18 PM

I appreciate the input, gents. I am probably going to hold off on any other performance upgrades (except an intake) until a legit tune comes available. I want to tailor my mods to the tune, plus I really enjoy the sound of the car as it sits. I actually like the sound with the valves closed as much as I like the open valved sound.

HitmanHearns · 07-12-2018, 12:43 PM

Quote:

Originally Posted by ericbilt

You will feel a sound difference with a catted down-pipe because the size of the cat is much smaller then the oem and the piping is larger, but it won't be loud like the cat-less. I just ordered a DS1 catted down-pipe and the MPE axle back exhaust so I'm hoping it will be a good combo.

Make sure when you put the catted downpipe on you drive off with at least one door open...

B58 · 07-12-2018, 04:12 PM

Quote:

Originally Posted by HitmanHearns

Make sure when you put the catted downpipe on you drive off with at least one door open...

Lmao

E90ROXS · 07-12-2018, 05:39 PM

car sound throatier with catted dp. It also pulls harder.

07-02-2018, 06:43 PM	#1
tobefair-idontcare Second Lieutenant 54 Rep 286 Posts Drives: BMW 340i Join Date: Jun 2018 Location: D.C. iTrader: (5)	Catted Downpipe Help This is a multi question thread for some collective forum help. I am interested in getting an aftermarket down-pipe down the road, however I don't really want to the sound to change from my current setup (MPPSK). I'm looking at purchasing a down-pipe with catalytic converter and my questions are: 1.) By keeping the car catted will my current exhaust sound remain the same? Not to the exact decibel level, but close. 2.) Will the power increase be on par with a catless system? 3.) What's the best down-pipe brand to go with knowing the information from the previous two questions? Any help would be appreciated. I'm open to advice, suggestions, guidance and recommendations. Thanks, gents! __________________ 17' 340ix\|Track Handling Package\|MPPSK\|MP Stage 2.5 ECU Tune\|MP Stage 2 Trans Tune\|AP Intake\|763M Wheels
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07-03-2018, 01:39 PM	#2
tobefair-idontcare Second Lieutenant 54 Rep 286 Posts Drives: BMW 340i Join Date: Jun 2018 Location: D.C. iTrader: (5)	Bump. Any help would be appreciated.
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07-03-2018, 01:58 PM	#3
G.Newt Major 806 Rep 1,452 Posts Drives: CT4-V Blackwing 6MT Join Date: Feb 2017 Location: CO -> TX iTrader: (0)	All aftermarket downpipes will increase sound. They're larger in diameter and the catted ones typically have a less dense (cspi) catalytic converter to allow more flow (sound). Power isn't much different unless you're trying to push big numbers. But anything aftermarket will perform better than OEM. __________________ 2022 CT4-V Blackwing 6-speed SOLD: 2016 340i xDrive 6-speed DAW v2.5 turbo E40 \| Dorch S2 \| VRSF DP \| MST intake \| AWE catback \| 335is clutch \| CSF heat exchanger \| RK Autowerks intake manifold \| Orange M Perf Brake Kit \| KW Street Comfort coilovers \| GTS taillights V2
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07-07-2018, 12:29 PM	#4
B58 Major 558 Rep 1,456 Posts Drives: 922 Turbo Join Date: May 2018 Location: USA iTrader: (1)	You will feel a sound difference with a catted down-pipe because the size of the cat is much smaller then the oem and the piping is larger, but it won't be loud like the cat-less. I just ordered a DS1 catted down-pipe and the MPE axle back exhaust so I'm hoping it will be a good combo. __________________ 2024 X3 M40i 2014 BMW M5
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07-07-2018, 01:00 PM	#5
BulsaraF36 First Lieutenant 142 Rep 352 Posts Drives: F36 435i M-Sport Join Date: Apr 2016 Location: Harrisburg, NC iTrader: (8)	I have Fabspeed catted dp installed along with MPPK/MPE and Dinan stage 3 when I recorded this video. __________________ 2016 435i M-Sport \| Carbon Black \| 20" 624M Wheels \| MPPK \| MPE \| M Performance Brakes \| M Performance Steering Wheel II with Display \| xHP \| Dinan Stage 4 \| Dinan Big Turbo \| Dinan High Performance Intercooler \| Dinan Intake \| Dinan Shockware \| Fabspeed Sport Cat Downpipe \| Custom Quad Tips \| Autotecknic Red Paddle Shifters
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07-07-2018, 09:18 PM	#6
tobefair-idontcare Second Lieutenant 54 Rep 286 Posts Drives: BMW 340i Join Date: Jun 2018 Location: D.C. iTrader: (5)	I appreciate the input, gents. I am probably going to hold off on any other performance upgrades (except an intake) until a legit tune comes available. I want to tailor my mods to the tune, plus I really enjoy the sound of the car as it sits. I actually like the sound with the valves closed as much as I like the open valved sound. __________________ 17' 340ix\|Track Handling Package\|MPPSK\|MP Stage 2.5 ECU Tune\|MP Stage 2 Trans Tune\|AP Intake\|763M Wheels
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07-12-2018, 05:39 PM	#9
E90ROXS Captain 225 Rep 676 Posts Drives: E90 Join Date: Feb 2012 Location: SJ iTrader: (1)	car sound throatier with catted dp. It also pulls harder.
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