Bimmerworld X-pipe impressions

[E92Bean]

Just installed a custom catless BW x-pipe with 2 extra sets of resonators. With my corsa rear section, this is a perfect setup imo. Zero drone, no rasp, and an exotic tone.
A proper tune is needed to optimize this setup, so I have an Epic Motorsports tune on the way.
I’ve been running this system without a tune, and I’ve found drivability to be fine. No CEL, but some stuttering at high rpm. Also, a slight buzzing/whirring on acceleration. I’ll see if it changes after tuning.

[darren p.]

curious how this works out, I have a similar setup but with high flow cats in the rear section. Epic, BPM or RK Tunes are the 3 I'm looking into, why did you go with Epic over the others?

[E92Bean]

Originally Posted by darren p.

curious how this works out, I have a similar setup but with high flow cats in the rear section. Epic, BPM or RK Tunes are the 3 I'm looking into, why did you go with Epic over the others?

Epic is known for tuning track ready s65 platforms, and prominent in bmw club racing. He’s perfected tuning the BW x pipe/forward x configuration too.
I will be tracking my m3 and I think the tune will be a good match.

[zcp312]

Originally Posted by E92Bean

Epic is known for tuning track ready s65 platforms, and prominent in bmw club racing. He’s perfected tuning the BW x pipe/forward x configuration too.
I will be tracking my m3 and I think the tune will be a good match.

Yes and yes exactly, Randy is great. What kind of secondary resonators did you get?

[E92Bean]

Originally Posted by zcp312

Yes and yes exactly, Randy is great. What kind of secondary resonators did you get?

The previous owner had the fab work done, and he said it was just what the exhaust shop had around so idk. The x-pipe has the magnaflow resonators in the standard position, with 1 set of resonators in the primary cat location and the other set as pictured after the x.

[zcp312]

Thanks, did the extra set of resonators eliminate the castless smell at all?

[spammysammich]

Originally Posted by zcp312

Thanks, did the extra set of resonators eliminate the castless smell at all?

They won’t.

[E92Bean]

Originally Posted by zcp312

Thanks, did the extra set of resonators eliminate the castless smell at all?

Nope, to eliminate any smell you’d mimic this modified BW x-pipe with HFC. Also, since my x-pipe is welded that eliminates potential leaks that could introduce more stink than usual.