[Willson1010]

Hey guys so I just ordered a VRSF catless downpipe for my 2016 340i xdrive. I currently have bootmod3 stage 1 flashed. I was just wondering if add the downpipe will make the car faster without the stage 2 tune. Obviously I know flashing stage 2 will help tremendously but I was just wondering if I could expect any gains just from the pipe since I'm in no rush to flash to stage 2. I'm mostly doing the upgrade for the sound. Any input would be greatly appreciated!

[435gc]

Should get a bit of hp. You would see that even without the tune. More so with the tune. You will also see improved throttle response/turbo spool.

[thejeremyman9]

My thread here might provide some insight: https://f30.bimmerpost.com/forums/sh....php?t=1710794

[Willson1010]

Originally Posted by 435gc

Should get a bit of hp. You would see that even without the tune. More so with the tune. You will also see improved throttle response/turbo spool.

Originally Posted by 435gc

Should get a bit of hp. You would see that even without the tune. More so with the tune. You will also see improved throttle response/turbo spool.

Thanks man, that's kind of the thought I was having too

[Willson1010]

Originally Posted by thejeremyman9

My thread here might provide some insight: https://f30.bimmerpost.com/forums/sh....php?t=1710794

That thread is a huge help. Thank you!

[Wires]

Personally, do S2 once you install the DP. It makes the car A LOT more fun. For me, winter tires and winter on S1 was fine traction control wise. With S2, you can now spin tires (AWD) so the gains are very real.

[razzy530]

get ready for that CHECK ENGINE light to stay on... I would stay away

[thejeremyman9]

Originally Posted by razzy530

get ready for that CHECK ENGINE light to stay on... I would stay away

Tune can disable this CEL. It's a non-issue if you want to deal with the other catless concerns (smell, emissions compliance, etc).

[Wires]

Originally Posted by razzy530

get ready for that CHECK ENGINE light to stay on... I would stay away

EVERY catless DP will give a CEL unless you install bypasses or tune out the CEL. Doesn't matter the brand -- you are missing the cats, so the top and bottom O2 have the same reading, which is showing no reduction.

[Willson1010]

The bootmod3 tune takes care of the check engine light right? That's what the local bmw performance shop told me. He said it would even pass inspection if I had the tune

[jmack]

Originally Posted by Willson1010

The bootmod3 tune takes care of the check engine light right? That's what the local bmw performance shop told me. He said it would even pass inspection if I had the tune

BM3 will clear the CEL but you won't pass NY inspection without slipping someone a hundred under the counter.

[thejeremyman9]

Originally Posted by Willson1010

The bootmod3 tune takes care of the check engine light right? That's what the local bmw performance shop told me. He said it would even pass inspection if I had the tune

If your state requires your catalyst emission monitor to be ready, obviously a catless DP will not pass. Some people have varied success with O2 spacers/mini cats, but that is a separate discussion. The tune removes the CEL but does not affect the emission monitor.

Originally Posted by jmack

BM3 will clear the CEL but you won't pass NY inspection without slipping someone a hundred under the counter.

I don't see how this works for a OBD2 check. They have to plug into the car. I've been doing this for 10+ years for sniffer tests (on older vehicles) since the machine is not connected to the car and therefore it can be in any tailpipe, but for a OBD2 test that connects to the car and is tied to VIN i don't see how this is a viable option. The only thing they can overlook is the visual and other parts of the check.