[askforcharliek]

just as an update, i ended up getting the m performance exhaust. had it installed today and am very happy. when driven in comfort and not pushing, it's just a notch over the sound of sport mode with factory exhaust. when driven in sport or sport + mode and driven hard it sounds great. very happy. i am hopefully done with the enhancements!!

[KD07]

Originally Posted by NYC_340i

So would you guys recommend a catless DP with everything else stock or a mid pipe with everything else stock? I know the DP is going to be better performance wise but how about sound?

Haven't heard a 340 with a downpipe in person yet, but I have a full catback. I'm pretty sure it will sound better with a downpipe at WOT, but idling and lightly accelerating you hardly notice a difference. Midpipes will sound better idling and lightly accelerating because it deletes the 2nd cat and resonator.

[E90ROXS]

Originally Posted by NYC_340i

So would you guys recommend a catless DP with everything else stock or a mid pipe with everything else stock? I know the DP is going to be better performance wise but how about sound?

You should get dp with exhaust. It will sound exotic. Remember to use the resonator. Otherwise it sounds really loud.

[riskmaker76]

Get a new mid pipe fron Dinan or sorts... will really open it up.

I have heard the M performance exhaust.. it wakens up with a mid pipe - essentially becomes a MPPSK sound..

Originally Posted by askforcharliek

just as an update, i ended up getting the m performance exhaust. had it installed today and am very happy. when driven in comfort and not pushing, it's just a notch over the sound of sport mode with factory exhaust. when driven in sport or sport + mode and driven hard it sounds great. very happy. i am hopefully done with the enhancements!!

[Big Nodge]

Originally Posted by G.Newt

I'm not familiar with NY laws, but most states don't require emissions testing for the first several years. Then it's followed by a period of OBD-II testing only, and finally after more years is where they do actual sniffer emissions testing. Since you're leasing, just keep the stock downpipe and swap back in when it's time to turn in. I wouldn't worry unless you plan on keeping the car afterwards.

That's a little bit dangerous as blanket advice, in my opinion. I've lived in Massachusetts and New Hampshire and both have annual emissions testing via the OBD system. Emissions compliance and readiness. That means if you have a DP, even a DP with a hi-flow cat, you'll have issues passing whether or not you have addressed the CEL with a tune. Because you can't pass with an emissions CEL, and you can't pass readiness if your tune disables an O2 sensor. O2 spacer did work for me in the past, but it was a hassle and part of the reason I've avoided the DP route on this car. This does not apply in every state of course, but it can def be a major pain.

[riskmaker76]

NY is the worst! They check for EVERYTHING! And the worst part is, if you fail they rip off your current sticker forcing you to fix it right then and there.

Personally catless down pipe in NY is too much hassle... just change the mid pipe and exhaust... Sounds beautiful...

[STR8-6IX]

Originally Posted by DrifterX

If you want more exhaust sound, get a mid-pipe... I'm thinking of eventually getting one for my car with the stock exhaust. There are some videos around of 340i with mid-pipe only. Cat-back isn't really worth the cost IMO.

Since you have a JB4, I've read a down pipe will help with performance a bit. Not sure if it'll be too much louder with a stock exhaust but you might hear more of the turbo.

Decide based on what you want.

catback is not worth the money at all. best to spend it on a downpipe+ tune instead.

[riskmaker76]

You mean axle back... Mine is cat back... Sounds bad?

Originally Posted by STR8-6IX

catback is not worth the money at all. best to spend it on a downpipe+ tune instead.

[STR8-6IX]

Originally Posted by riskmaker76

You mean axle back... Mine is cat back... Sounds bad?

sounds awesome but I would always pick a catless downpipe + ecu tune vs a catback its the same money but DP has much better gains. it will still sound great, but your mppsk's exhaust system is beautifully refined. loved the sound.

I'd do a catless downpipe and catback if I was really balling but that would be like ear-rape levels of sound. I just cant justify spending 1000+ not including installation for this awesome sound if you get so much more performance out of the downpipe for similar money.

[STR8-6IX]

Originally Posted by riskmaker76

You mean axle back... Mine is cat back... Sounds bad?

heres my current exhaust setup in comparison.. obviously no MPPSK but for $500 im not complaining either. its louder and sounds better in person. I just need to get rid of that shitty magnaflow... its not a bad muffler especially for the money - but it drones. at least this mufflers low, smooth tone is really well suited to a straight 6 exhaust sound. this is a naturally aspirated n52.

most of all, I'm upset I cant tune my ecu. really want catless headers.

[riskmaker76]

Living in the people's socialist state of ny, catless down pipes are headaches with inspections... also causes all sorts of issues without a tune (ewasiky fixed with jb4)

For me remove the resonators and change he exhaust... fixes all sound issues .

Add a jb4 and intake ..... your at 400 hp...done..still passes emissions no headache

[iMinLuv]

Originally Posted by riskmaker76

Living in the people's socialist state of ny, catless down pipes are headaches with inspections... also causes all sorts of issues without a tune (ewasiky fixed with jb4)

For me remove the resonators and change he exhaust... fixes all sound issues .

Add a jb4 and intake ..... your at 400 hp...done..still passes emissions no headache

Just move to a red state in indiana we don't have emissions testing at least not in my or surrounding county's .

I have a hi flow catted downpipe I don't know the specifics of each state but it made a pretty noticeable change and the CG Precision pipe supposedly doesn't throw a cell. I have had the JB4 the entire time I've had it so can't really comment. I have run Map zero a few times though and no issue.

I wasn't totally happy with the note and volume until I went DP mid pipes and exhaust.

Started with just exhaust the note was perfect but not quite loud enough. Added downpipe and then it was really good but once the mid pipes went in it was perfect (for me). I like the Dinan because it's super deep and not crazy obnoxious. My set up has zero drone.