M5 Downpipes experts and gurus? How and why?

[soooma]

Simple as that,
I tried to read up and I did and I know some about how and why M5 Downpipes work,
But what I don't know
1. Real M5 owners experience with Catless 1250$ vs 2500$ catted I was quoted
2. How they really work with M5 F10 and turbos which is the real reason for gain and how's the car engine compartment bay doing on room?
3. Living in North Carolina ? Will it pass catless?
4. End of lease is coming up in 18 months ! Am I gonna have to replace genuine back ? Probably to get some of my money back?
5. Measly 30 hp gain is really noticeable ? How come when I'm already suffering with lack of traction with 560 hp?
6. Sound gain is good?

Thank you so M5 gurus - ,
Waiting for answers to pull the trigger

[boots]

Ya killing me! Lol. Cat vrs Catless. Less weight and no cats to deal with. Price diff because there are no cats = less price. Smoother bends means better flow= more power. Lease ends change them back and turn in car. Sell dp afterwards. Power you can actually feel and awesome sound increase. Fun factor 100%. This is a no brainer power increase. Get a tune and don't worry about inspections. Faster car=yes!

[bigfra]

Originally Posted by boots

Ya killing me! Lol. Cat vrs Catless. Less weight and no cats to deal with. Price diff because there are no cats = less price. Smoother bends means better flow= more power. Lease ends change them back and turn in car. Sell dp afterwards. Power you can actually feel and awesome sound increase. Fun factor 100%. This is a no brainer power increase. Get a tune and don't worry about inspections. Faster car=yes!

Fuck aye, I bought ss catted downpipes and still get cel. Get non catted wans.

[boots]

Yea seems everyone who bought them got a cel. When you get a tune they will remove that light, remove speed limiter , and add power. Believe me it works :)))))

[darkz]

I haven't seen any car with catless DP run without a CEL yet, unless there is something wrong with the system itself, must need a tuner to remove this, catless also make the car louder, depends on your personal preference, sometimes I regret getting catless on my other cars, gets too loud and the wife hates it....

[The Goose]

Other than the annoying light being on is there any mechanical issue to worry about with CEL and catless DP's? I have an Akra exhaust and Undercover Tuning DP's I'm going install after my 1200 mile service.

[6spdterror]

I have the catless DPs from undercover and i dont get any CEL obviously because i have a full ECU tune but i will tell you this......it smeels like fumes if youre driving with windows open and u stop at a light! That gets annoying. Of course...the wife hates the smell and sound! To me it sounds amazing!!

[darkz]

you would be running alot richer on fuel if just catless DP installed without tune, without cat it does stink alot

[The Goose]

Thanks. I'm not worried about the smell as I've driven cars without cats before. I will get a tune eventually.

[UnfoundLegend]

Sooma you have resonator delete right??

First thing I did after getting exhaustmeister was the catless downpipes. Best decision ever.

For me, it wasn't quite loud enough at higher RPM's on the test drive with just the catless downpipes, and I didn't have the exhaustmeister remote on me at the time (stupid I know), so I had the shop remove resonators and they claimed at the time that it would create massive unnecessary drone and almost no sound gain. I just told them to do it anyway and am I glad I did...!

With exhaustmeister it is as loud as you can possibly get without drone. Absolutely no drone with the valves closed. Perfect for the highway not a single sound from the exhaust in higher gears. Oh and I'm in an M6 by the way, in which the drone would probably be more pronounced.

So hurry up and do it before your lease is up! The only thing you'll regret is why you didn't do it earlier (and some mornings the enormous cold start).

[boots]

Originally Posted by 6spdterror

I have the catless DPs from undercover and i dont get any CEL obviously because i have a full ECU tune but i will tell you this......it smeels like fumes if youre driving with windows open and u stop at a light! That gets annoying. Of course...the wife hates the smell and sound! To me it sounds amazing!!

That smell will go away in time with more miles on your dp.

[M6-Coupe]

How do you guys deal with CEL? isn't it annoying?
and don't you have any issue when you go to dealer for service?

[boots]

That's what the Cann tool was for. Tool the cel away.

[6spdterror]

Originally Posted by boots

That smell will go away in time with more miles on your dp.

Are you sure?!? Or are you just used to it by now!? It seriously had me contemplating swapping out for a catted DP because i love to drive with my windows down

Originally Posted by M6-Coupe

How do you guys deal with CEL? isn't it annoying?
and don't you have any issue when you go to dealer for service?

No CEL here. Im fully tuned by Enzo Performance so no speed limit or CEL

[boots]

I have lots of people in my car at diff times. They can't smell any odor and ive asked them if they can smell exhaust fume. It lasts for a while but I've got thousands of miles on my dp so it's well worn in.

[darkz]

I thought thats why the cat is there to catch the smell? I have had my cat removed on my truck for a year now, and the smell is still going strong, almost want to change it back to catted DP.

[darkz]

Originally Posted by 6spdterror

Are you sure?!? Or are you just used to it by now!? It seriously had me contemplating swapping out for a catted DP because i love to drive with my windows down

I dont think you can smell it while the car is rolling, considering the smell only come from behind. it stinks while is idling.

[AntoM3]

I've had AMS catless for a couple hundred miles now. I was definitely speculating getting downpipes but I'm honestly so glad I did. Yes it does smell, yes you do feel gains, yes it does sound amazing. Downpipes changed the whole demeanor of the car. The CEL is not that annoying IMO but I will be getting a tune soon to take care of it.

[MFIZZLENYC]

So far Loving My Noelle Catted downpipes a few more hp and NO smell or SES light

[URBAN LEGEND]

The smell of raw fuel never goes away. You are taking out the cats/their magic and running straight pipes. Been there, done that, never again.

[A Frankfurt]

Originally Posted by M6-Coupe

How do you guys deal with CEL? isn't it annoying?
and don't you have any issue when you go to dealer for service?

Yes if you have a drivability issue and your under warranty, the dealership will hassle in regards to the CEL being on.
A few of my clients that went to 3 different dealerships in CA all had to have me reinstall the factory cats before they would do the diagnostic.
And the issue was no emission related.

[6spdterror]

Its the raw fuel smell when i stop at a light. Its never there whilst im driving or if my windows are shut. I love to drive with my windows down so its especially an issue for me. I dont want my car smelling like fuel everytime i stop at a light or i start it up in an indoor parking garage. Im seriously wondering how much HP ill lose by going to catted DPs and if ill get the same amazing sound and cracks!