[wassy4]

Originally Posted by G.Newt

You will get some gains with a DP. How much? That depends. Obviously with a tune you'll reap the most benefits, but I don't have one.

I know I've been posting this everywhere, but I dyno'd 344 hp / 355 torque, then 333 hp / 375 torque. Mods are in my signature. I don't think the intake/exhaust is doing a whole lot. I think most of my gains are from the DP.
Depending on how much you up the boost with the JB+, you may start to see throttle closures. These can be somewhat or mostly remedied with EWG wires as an add-on for the JB4.

JB+ won't get you close enough to the fuel cap to experience throttle closures. It will most likely happen with one of the big boy tunes though, at least in cold weather.

Also Rob340i , you'll notice a very slight difference in power but a big difference in throttle response. You'll be completely fine running a JB+ and downpipe though, just not as much power as JB4. You'd be missing out on power anywhere from 20-40 horses.

[G.Newt]

Originally Posted by wassy4

JB+ won't get you close enough to the fuel cap to experience throttle closures. It will most likely happen with one of the big boy tunes though, at least in cold weather.

Also Rob340i , you'll notice a very slight difference in power but a big difference in throttle response. You'll be completely fine running a JB+ and downpipe though, just not as much power as JB4. You'd be missing out on power anywhere from 20-40 horses.

Do you experience TC with your Active-8 and DP? That's the tune I'm leaning towards once the warranty is up.

[wassy4]

Originally Posted by G.Newt

Do you experience TC with your Active-8 and DP? That's the tune I'm leaning towards once the warranty is up.

Rarely but it has happened before. Usually happens when temp drops below 50 degrees, otherwise it's usually pretty smooth.

[Rob340i]

Thanks for all the info sorry to hijack thread OP please continue lol

[340ix17]

For those who have purchased the ER catted DP in states with tough emission laws, does this force you to place the stock DP back on for inspections, or is it possible to have it pass still on the vehicle (meaning all 'readiness' stages pass, and the DP on it's own will not throw a CEL with a tune removed)?

I'm in MA, and contemplating the ER catted to go with my JB4, but thinking that it's unclear to me whether the car will be able to reach the state of 'readiness' when the tune is on, and how much this is exacerbated by having a catted downpipe

[blckz06]

Originally Posted by 340ix17

For those who have purchased the ER catted DP in states with tough emission laws, does this force you to place the stock DP back on for inspections, or is it possible to have it pass still on the vehicle (meaning all 'readiness' stages pass, and the DP on it's own will not throw a CEL with a tune removed)?

I'm in MA, and contemplating the ER catted to go with my JB4, but thinking that it's unclear to me whether the car will be able to reach the state of 'readiness' when the tune is on, and how much this is exacerbated by having a catted downpipe

You should be fine. I have a catless ER DP with a jb4 and have no issue CELs. Even if it comes up, just clear it and drive sedately for a few days to check all the readiness stages and you should be good.

[B58]

Originally Posted by 340ix17

For those who have purchased the ER catted DP in states with tough emission laws, does this force you to place the stock DP back on for inspections, or is it possible to have it pass still on the vehicle (meaning all 'readiness' stages pass, and the DP on it's own will not throw a CEL with a tune removed)?

I'm in MA, and contemplating the ER catted to go with my JB4, but thinking that it's unclear to me whether the car will be able to reach the state of 'readiness' when the tune is on, and how much this is exacerbated by having a catted downpipe

This is the only o2 spacer that has worked for me: https://www.hstuning.com/42-draft-de...or-spacer.html

I have had this spacer since my previous 2016 GTI and it has been removed and installed on my current 340i. I been catless for over 1,000 miles and have not had a check engine light turn on for anything related to the down-pipe.

[335i/335d?]

I have an mppsk 340i and I am thinking of a downpipe as well. However I like the sound as it is, only buying it to run an higher stage tune. Think the mppsk is loud enough. Dont mind buying a catted downpipe if this doesnt restrict me on power.

[B58]

Originally Posted by 335i/335d?

I have an mppsk 340i and I am thinking of a downpipe as well. However I like the sound as it is, only buying it to run an higher stage tune. Think the mppsk is loud enough. Dont mind buying a catted downpipe if this doesnt restrict me on power.

Catted down-pipe wont restrict you on power. The down-pipe diameter is larger and the high flow cat inside is half the size of the oem if anything you will gain additional power. I have a friend with a MPPSK 340i with the VRSF catted down-pipe and its loudly perfect. I had the CG 5" catted down-pipe and switched recently to a VRSF 4.5" catless down-pipe and did not feel a difference power-wise except for the car smelling more like shit and a bit more of pops and bangs. If i wasn't planning on going Pure I would of just kept the catted down-pipe.

[340ix17]

Originally Posted by B58

This is the only o2 spacer that has worked for me: https://www.hstuning.com/42-draft-de...or-spacer.html

I have had this spacer since my previous 2016 GTI and it has been removed and installed on my current 340i. I been catless for over 1,000 miles and have not had a check engine light turn on for anything related to the down-pipe.

Thanks, not sure how bad the emissions laws are in CA, but I'm pretty sure I can safely assume they are probably as bad as MA.

Just to be clear, do you plan on passing emissions with the DP installed, or have you already passed?

I just don't want to have to take it on/off each year for inspection, that would be a PIA.

[340ix17]

Originally Posted by blckz06

You should be fine. I have a catless ER DP with a jb4 and have no issue CELs. Even if it comes up, just clear it and drive sedately for a few days to check all the readiness stages and you should be good.

Were you happy with the catted ER, and how are the noise/performance increases? ER is looking a little more affordable than the CG DS-1 at the moment

[flyknit]

I’m considering between ER catless and catted, more towards catted as welL

[G.Newt]

Originally Posted by 340ix17

Were you happy with the catted ER, and how are the noise/performance increases? ER is looking a little more affordable than the CG DS-1 at the moment

I was faced with that same dilemma a year and a half ago. I went with the CG DS-1. At that time, there were no reports of CEL but the ER had a couple. I'm not sure if those facts still stand on these forums, but nearly 10k since installation and all I've gotten is more power, sound, and smell lol. No CELs.

EDIT: The DP was also only $680 compared to its nearly ~$1k price tag. So that also is a big factor. I'd probably go with a catted ER and a DP fix just in case now all things considered.

[mike@x-ph.com]

Originally Posted by flyknit

I’m considering between ER catless and catted, more towards catted as welL

[flyknit]

Originally Posted by G.Newt

I was faced with that same dilemma a year and a half ago. I went with the CG DS-1. At that time, there were no reports of CEL but the ER had a couple. I'm not sure if those facts still stand on these forums, but nearly 10k since installation and all I've gotten is more power, sound, and smell lol. No CELs.

EDIT: The DP was also only $680 compared to its nearly ~$1k price tag. So that also is a big factor. I'd probably go with a catted ER and a DP fix just in case now all things considered.

Because of the smell?

[G.Newt]

Originally Posted by flyknit

Because of the smell?

No, it's not that bad, but it does smell more. More so because of the significantly increased cost. It's not $300 better than it was before.

[blckz06]

Originally Posted by 340ix17

Were you happy with the catted ER, and how are the noise/performance increases? ER is looking a little more affordable than the CG DS-1 at the moment

Yes, perfectly happy. Although it's a catless pipe. I got jb4 and the pipe at the same time so performance is hard to comment on. I have no resonators (MPPSK) so it's pretty damn loud. It did quiet down after the first few months.