[Khy335i]

Thought i'd show you guys know the gains i got after installing a VRSF catted downpipe. I was quite surprised and so was the tuner after seeing the results considering the downpipe is catted!! Props to VRSF!!

That's approx. +14kW/20bhp

[Tiago@VRSF]

Glad you're enjoying the downpipe!

[mike@x-ph.com]

Good gains

[JunkyardDogg]

Nice! How much different does it sound from stock or catless?

[nOEMm]

Forgive the ignorance, is there any worries about passing emissions with the catted option? Ik u definitely have to take steps to pass with the catless, but are you guaranteed good to go should you opt for the catted??

-someone who really wants a dp but is afraid of consequences

[Tiago@VRSF]

High flow catted DP's will generally only throw a code at high RPM under excessive load. Idle/cruise conditions are fine and don't generally trip codes.

[Johnny Boost]

Originally Posted by nOEMm

Forgive the ignorance, is there any worries about passing emissions with the catted option? Ik u definitely have to take steps to pass with the catless, but are you guaranteed good to go should you opt for the catted??

-someone who really wants a dp but is afraid of consequences

Get a DP fix. Problem solved.

[WiL335i]

Originally Posted by Johnny Boost

Get a DP fix. Problem solved.

Is there a downpipe fix now for N55 platform?

[Khy335i]

Car sounds and feels better! but do not expect anything massive cause you just won't get it with a catted dp. Dyno results speak for them self.

I've been thrashing the car around and have yet to see any codes, have not smelt anything more than I usually do in terms of emissions - maybe a little at the start but that could of just been the paint/steel on the new dp just working it in. IMO car still smells stock.. if you could use that as a reference to pass emissions lol

If a code DOES show you could just delete it with a JB4, that is if you have it..otherwise not sure if there are any deletes

[AirbusPilot]

Very cool.

[Jeff@TopGearSolutions]

Originally Posted by WiL335i

Is there a downpipe fix now for N55 platform?

Yes, VRSF

[mike@x-ph.com]

VRSF catted Downpipes pictures

[nOEMm]

If this dp was paired with a cobb/mhd tune that cleared codes, would there be any need for one to still buy the dp fix as far as emissions testing is concerned?

[OneMoreAlex]

Originally Posted by nOEMm

If this dp was paired with a cobb/mhd tune that cleared codes, would there be any need for one to still buy the dp fix as far as emissions testing is concerned?

These are catted downpipes so no DP fix would be needed.

Cobb/MHD/JB4 will not pass emissions on catless downpipe it will only mask the code so you're not staring at a check engine light, that's where DP fix comes in.

[maddmatth]

Are there any comparison tests with stock downpipve vs VRSF catted vs Catless?

I wonder if it would also work well to go with catless downpipes then have a good aftermarket cat welded into the exhaust, moves the restriction further from the turbo?
Personally I'd never want to go completely catless for a daily driver.

[aaron_]

Originally Posted by maddmatth

Are there any comparison tests with stock downpipve vs VRSF catted vs Catless?

I wonder if it would also work well to go with catless downpipes then have a good aftermarket cat welded into the exhaust, moves the restriction further from the turbo?
Personally I'd never want to go completely catless for a daily driver.

That's exactly what I'm doing next sat. Was meant to be tomorrow, but got rescheduled to next week. Theoretically seems like a better option to me

[Achappell8]

Originally Posted by maddmatth

Are there any comparison tests with stock downpipve vs VRSF catted vs Catless?

I wonder if it would also work well to go with catless downpipes then have a good aftermarket cat welded into the exhaust, moves the restriction further from the turbo?
Personally I'd never want to go completely catless for a daily driver.

Out of curiosity since DPs are on the horizon for me, why would you never go catless on a daily?

[jeanlucdckhard]

Originally Posted by Achappell8

Out of curiosity since DPs are on the horizon for me, why would you never go catless on a daily?

Agreed. Would like this answer as well

[Rob_BMW_PNW]

Originally Posted by OneMoreAlex

These are catted downpipes so no DP fix would be needed.

Cobb/MHD/JB4 will not pass emissions on catless downpipe it will only mask the code so you're not staring at a check engine light, that's where DP fix comes in.

If your readiness show 'ready' it will

I have a N54tuning catless N55 DP on my 135i, MHD tuned, all of my vehicle parameters read 'ready' except for EGR or Evap I dont recall.
Both o2 sensors read ready after a short drive. I actually reset my ecu today because I got a MAF code (no SES on dash, I just happened read codes), and by the time I got to work both o2 sensors were 'ready'


Your will pass as long as it has 1 or less 'not ready'

[GripAndRip]

Originally Posted by jeanlucdckhard

Agreed. Would like this answer as well

I think smell is the primary reason it's avoided. No one is avoiding giving their daily driver a little umpff. But they want that power increase without having their car smell like a racecar.

I feel like the fear of DPs can be summed up to the following:

Smell
Emissions Passing
Noise level

[Kevin39]

Yep,I went with catted for smell and noise.

[GripAndRip]

Originally Posted by Tiago@VRSF

Glad you're enjoying the downpipe!

If you don't mind me asking, what are your claimed gains on a catless DP with a tune? 30BHP? I'm not sure what options the OP is running on his car, but I would love a comparison between the two options. It would definitely justify the price of the race cat, seeing that it would eliminate smell and debatably give roughly the same gains.