Installing an ER downpipe on an F15 X5 x35i next week, need experienced input.

[gregkiel]

I have a 2 post lift and just about any tool imaginable at the shop that I'm doing the install at.

I've done a downpipe on a 335i N55 and it was kind of a pain in the ass getting the right combo of extensions to get to the turbo side of the dp.

Can the dp on the F15 be removed and reinstalled in the same fashion as the 335i N55? What tips do you have for installing a DP on this platform? Any advise would benefit me in reduced lift time, and would be much appreciated!

Thank you

[M302_imola]

Curious as to what improvements you saw from the downpipe upgrade in your 335i?

[gregkiel]

Originally Posted by M302_imola

Curious as to what improvements you saw from the downpipe upgrade in your 335i?

Not my 335i, a friend's, but from what I remember the sound was harsher, the turbo spool seemed faster, and it definitely felt like it picked up power.

[Brooks1NC]

I just got a tune, intake, charge pipe, and down pipe on my 2014 35i and now I have an engine light on! The code is PO420 which is cat related. Anyone have any insight?
Thanks!

[gregkiel]

Originally Posted by Brooks1NC

I just got a tune, intake, charge pipe, and down pipe on my 2014 35i and now I have an engine light on! The code is PO420 which is cat related. Anyone have any insight?
Thanks!

Yeah, it will absolutely throw O2 codes. The stock DP is where the cat is located and those O2 sensors read there. The DME is looking for stock O2 readings which it wont get, as you aren't catalyzing. If you have high flow cats you can spacer the O2 sensors to pull it out of the stream and trick the DME. If you are catless, you either need a signal generator or a flash tune. For myself, I do a flash tune as it is easier, and let me use an ER catless. Do an MHD Stage 2 or 2+ tune, and when you are flashing options make sure you untick the stock cat option. It will delete that engine code permanently.

[M302_imola]

Originally Posted by gregkiel

Yeah, it will absolutely throw O2 codes. The stock DP is where the cat is located and those O2 sensors read there. The DME is looking for stock O2 readings which it wont get, as you aren't catalyzing. If you have high flow cats you can spacer the O2 sensors to pull it out of the stream and trick the DME. If you are catless, you either need a signal generator or a flash tune. For myself, I do a flash tune as it is easier, and let me use an ER catless. Do an MHD Stage 2 or 2+ tune, and when you are flashing options make sure you untick the stock cat option. It will delete that engine code permanently.

Not to get off topic but what type of gains did you see from said combo?

[gregkiel]

Originally Posted by M302_imola

Not to get off topic but what type of gains did you see from said combo?

130HP to the crank. More if you upgrade your fueling.

[turboawd]

Originally Posted by gregkiel

130HP to the crank. More if you upgrade your fueling.

130 hp from a downpipe? Or what else you have?

[gregkiel]

Originally Posted by turboawd

130 hp from a downpipe? Or what else you have?

No. He is asking what gains over stock do you get from an intake, chargepipe, catless dp, and a mhd stg 2+ flash tune.