[LYTSOUT]

Like many of you, I thought a LOT about catless vs catted downpipes. I won't rehash the entire arguments about each one here b/c that's been done in countless threads (most of which I've read and a few I've commented on!). Suffice it to say, I was initially very concerned about the horror stories I've read about the smell from catless: "it gives me a headache, "my wife insisted I take it off", and even "pedestrians give me dirty looks from the sidewalk"! At the same time, I also wanted maximal performance while best sound was third on the priority list after smell and performance.

Anyway, just when I had pretty much made up my mind to go with catted, a track buddy of mine *gently* reminded me that many, if not most, of the cars at the track are catless. He said "you know that 'race car' smell at the track? Does that bother you? That's all the catless cars". That single phone call moved the needle enough such that I ended up getting a VRSF Catless downpipe.

I don't have any pics of the installation b/c I had a shop install it, but it looked great and the ones I do have are attached.

Performance: Holy cow does this thing wake up the car! Revs more freely, spools faster, and definitely added some ponies per the butt dyno just in BM3 Stage 1. Once I flashed to BM3 Stage 2, this car became an entirely new animal. A couple days later, I deactivated xDrive via xDelete and it was another huge transformation. I can absolutely roast the tires all day long from a standstill with DSC deactivated through not only first but it'll continue to spin them through second gear! Even with DSC on, I'm breaking them loose pretty much anytime I want in 2nd and sometimes even 3rd!

Drag race F30 BM3 Stage 2 6MT vs F80 ZCP DCT
TL;DR: they're damn near equivalent. For all intents and purposes, at normal/legal speeds, a Stage 2 F30 is absolutely as fast as an F80.

Drag Race Extended cut: I have not gotten a dyno b/c I don't plan to tune the car further, but I did do several stoplight-to-stoplight drag races against my dad in his F80 ZCP with DCT. Unfortunately I didn't think to record any of it, but what I can say is that on our best run where we both had the cleanest/equal launches, the cars were literally exactly side-by-side through first and all the way through the top of 2nd (in my car). Once I shifted into 3rd, he started to pull away and I wasn't able to catch him. I suspect this is due to the combo of his DCT and higher redline. Oh, and I had to "cheat" and flash it back to AWD to get the best launch. When I was in RWD, it was too hard to get the rear end to hook up thanks to all that new-found glorious torque. So, the bottom line is that, at regular (legal) speeds in traffic and from stop lights/etc (where most of us do the vast majority of our driving), a Stage 2 F30 is essentially F80-fast. It's not until 3rd gear or >70mph that the F80 really flexes its extra muscle.

Sound: It sounds awesome. IMO, this is no need to spend the money on a catback exhaust. A catless DP mated to the stock exhaust (with both flaps locked open) is just about perfect. Cold start is AMAZING. It's a bit more "tinny" or hollow sounding. It's hard to explain, but you'll know it when you hear it, and its not bad, just different. There are also way more whooses and spooling sounds from the turbo. Oh, and the burbles...they're insane. I had them turned up full blast with the OEM DP, but as soon as I had the catless DP installed, I had to dial the burbles WAY back b/c it sounded like a damn machine gun once I installed the DP. It was the very first thing I did when I got home from the shop b/c I was actually embarrassed to be driving a machine gun car through my neighborhood. Attached are some unedited clips of cold starts. I'm not sure the camera does it justice, but trust me, it sounds awesome.

Stock downpipe, stock exhaust, flap open:

VRSF catless downpipe, stock exhaust, flap open:

[Note: I did several different cold start videos in successive days b/c the camera on the iPhone kept annoyingly cutting out the sound at the exact same spot in each catless video. I'm not sure why, but I suspect there's some frequency that didn't jive with with mic on the iPhone. Anyway, I gave up after about the fourth one so that's the best I've got.]

Smell: Yes you can smell it, but only with the windows down in traffic and a little bit when I pull into the garage and get out of the car, but it doesn't bother me at all. In fact, when I came home from the shop, my 6yo son was standing in the driveway and said:
-Daddy, that smells SWEET!
-Wait...did you just say smells sweet or sounds sweet?
-Smells!
-Sweet as in cool?
-No, sweet like I wanna eat it!

So it passed the family nostril test in the first 10 seconds

Value: 10/10. I would absolutely do this mod again, and I'm really happy I went catless. I got the most performance, the best sound, and the only downside (smell) isn't an issue. Plus they're WAY cheaper than catted.