Equal Length Section 1 Opinions

[332]

Once you're past the where the primary pipes merge into a 3-1, or 6-1 etc the system really just shapes the torque curve below the peak torque rpm. If the system is overall highly restrictive then yes there can be gains at top end

So noting the observations

- 3hp (0.6%) is within the noise of system when you look at how the runs repeat back to back so there is nothing to see here from power perspective
- the Z lost the same or slightly more in the middle so it isn't scavenging better as that would be where a real difference would exist if it was scavenging better
- the X-pipe in question isnt even a good design due to the included angle (a necessary evil on a V8)

it makes perfect sense that nothing significant happens its fundamentally the same

The X-Y-Z-H pipe is not the place to spend uber money for topend power its a bottom end and mid range thing, probably do ok for IG likes;

I don't want to get this thread too far OT, however. This dyno shootout was interesting considering what you are stating. https://www.youtube.com/watch?v=7LEzdo8_93M for some bmw context, Akrapovic exhaust for the S85 has an H pipe, then an X pipe in their 8k exhaust. Edit: It's 3whp, so roughly 6hp Double Edit: Steeda is manufacturing the HX pipe now, after those dynos.

[332]

The owner is a scumbag that went nuts on customers after a dyno was done proving this thing has zero gains. It's in the E39 M5 Owners FB Group. Do not recommend.

I saw that, shame. You guys can have these fabricated for much less than 1k.. Just some idea's for all the section 1, crazy's out there. I feel like an x or h or both in the section one would have some benefit. shrug

[bmw m3 s50]

Here you go guys.

Before:



After:



I think this is the first modded 2.5” equal length section with cats and the slip fit to attach to Supersprint v1 stepped headers.

[0-60motorsports]

Here you go guys.

Before:



After:



I think this is the first modded 2.5” equal length section with cats and the slip fit to attach to Supersprint v1 stepped headers.

Awesome! Did you do that? What cats?

[Cubieman]

I just want one so I can look up at my car on the lift and see all these shit crazy bends/pie cuts, makes a regular section seem so boring!

I would be interested in something for the SSV1's like above if ever the price isnt too crazy, interested to see if/how much the sound changes.

[bmw m3 s50]

Awesome! Did you do that? What cats?

Yep, took a Rogue Engineering pipe, which is the only 2.5" equal length section 1 on the market (that I am aware of) and modified it. I added GESI (EPA rated) cats and the slip fit flange for the Supersprint V1 stepped headers. I went with GESI cats because 1) I got a good deal on them, and 2) they are 4" round diameter which was the same diameter of the original Rogue Engineering resonators that were on the equal length pipe.

My exhaust setup will be:

Supersprint v1 Stepped headers
Rogue Engineering equal length Section 1 with cats
Supersprint 2.5" dual pipe - resonated Section 2
Miestershaft titanium muffler

[0-60motorsports]

Yep, took a Rogue Engineering pipe, which is the only 2.5" equal length section 1 on the market (that I am aware of) and modified it. I added GESI (EPA rated) cats and the slip fit flange for the Supersprint V1 stepped headers. I went with GESI cats because 1) I got a good deal on them, and 2) they are 4" round diameter which was the same diameter of the original Rogue Engineering resonators that were on the equal length pipe.

My exhaust setup will be:

Supersprint v1 Stepped headers
Rogue Engineering equal length Section 1 with cats
Supersprint 2.5" dual pipe - resonated Section 2
Miestershaft titanium muffler

Very nice! Great work.

[theOracle]

Arrived Yesterday

Okay, I was able to get this installed today. I didn’t perform the installation myself as do don’t have the ability to get under the car like that. The shop I used had installed sections 1,2,3 for me last year.

They said install and fitment went on without trouble. It is 2.5” all the way.

The only thing that got in the way was a section of undercarriage cover ( BMW 51717892122). Rather than trim it they removed it and gave it to me.

The most important part is the sound. I belong to the “no rasp” camp. My main goal is to make the exhaust sound clean and not distract from the carbon intake plenum. I want amplify what sounds good and that hasn’t been the exhaust.

Exhaust setup as today:

Megan Racing headers (cera coated and Flo coated)
Bomiz Equal length catted section 1 (2.5” piping)
Supersprint resonated x-pipe section 2
Supersprint Sport muffler


VERDICT- success! The exhaust sounds smoother and doesn’t have any rasp. It has a great tone and is plenty loud. There is zero drone at any rpm. Above 4k rpm the airbox takes over and sounds unlike any other car on the road.

While the cats on this Bomiz can’t be best, they are doing a pretty good job. I ran without cats last year the smell was significantly stronger.

[M3stow]

Okay, I was able to get this installed today. I didn’t perform the installation myself as do don’t have the ability to get under the car like that. The shop I used had installed sections 1,2,3 for me last year.

They said install and fitment went on without trouble. It is 2.5” all the way.

The only thing that got in the way was a section of undercarriage cover ( BMW 51717892122). Rather than trim it they removed it and gave it to me.

The most important part is the sound. I belong to the “no rasp” camp. My main goal is to make the exhaust sound clean and not distract from the carbon intake plenum. I want amplify what sounds good and that hasn’t been the exhaust.

Exhaust setup as today:

Megan Racing headers (cera coated and Flo coated)
Bomiz Equal length catted section 1 (2.5” piping)
Supersprint resonated x-pipe section 2
Supersprint Sport muffler


VERDICT- success! The exhaust sounds smoother and doesn’t have any rasp. It has a great tone and is plenty loud. There is zero drone at any rpm. Above 4k rpm the airbox takes over and sounds unlike any other car on the road.

While the cats on this Bomiz can’t be best, they are doing a pretty good job. I ran without cats last year the smell was significantly stronger.

Hey it’s been a little over a month. Are you still satisfied with the cats smell and rasp elimination? The bomiz catted is still on presale. Seems like a great deal for under $700.

[theOracle]

I can’t give any new feedback because after posting last month I was gone for a week on business and then came back to have ACL replacement surgery. I’m 2 weeks removed from surgery. Making good progress but not enough to drive the M3. My plan is next week, 🤞🤞

[Mustafa564]

I can’t give any new feedback because after posting last month I was gone for a week on business and then came back to have ACL replacement surgery. I’m 2 weeks removed from surgery. Making good progress but not enough to drive the M3. My plan is next week, 🤞🤞

Any updates on the bomiz section 1? Cat holding up well?

[M3stow]

I can’t give any new feedback because after posting last month I was gone for a week on business and then came back to have ACL replacement surgery. I’m 2 weeks removed from surgery. Making good progress but not enough to drive the M3. My plan is next week, 🤞🤞

I ordered a HFC version today. $745 delivered. Should be here mid December. I’ll post some impressions when it gets here.

My setup will be:
Megan racing headers
Bomiz HFC sec 1
stock resonated sec 2
dinan sec 3