S54 Header Design talk

[Sharocks]

I suspect there will be a lot of V1s for sale when this project is concluded-- including mine.

I'll join you in this if they prove to do what we hope they do.

I'm just skeptical is all.

Very curious what these would cost to produce once finalized/optimized.

[Sharocks]

This raises a good point that at some point the system needs to be compared to probably euros and V1s and you need good data to do that on some kind of healthy controlled test mule of representative level of modification. Pretty much all of the exhaust roller chassis dyno test data is questionable if you want to see small gains which is potentially all that we are looking at for most engine specs.

If we're only testing this on stock S54s I'm sure some of that data is mostly transferable to more built engines but I do agree.

For example, I know KK's and Epics are better for high RPM use than low RPM use.

ARH and their reps are basically the same thing if you can even get them tuned correctly.

We have solid baselines for Euro and V1 and V2 setups so folks can make their purchases based on their builds.

I will also be hanging out with a friend this weekend who has access to a set of Motorsport Inconel headers. He told me they're absolutely useless down low but I already knew that. Maybe I can snag some dimensions from him if needed but I don't think those would provide anything of value to a street car.

[Bry5on]

Here's 500mm equal length (+/-0.5mm) stepped headers - single step from 40mm OD to 45mm OD. Secondaries are also equal length +/-0.1mm and have 100mm of straight section for a merge collector. There's even a straight shot to install every fastener except one. And enough clearance to the frame rail to get the headers over the studs for install in situ.

I'm not sure packaging the bigger OD is going to be achievable with equal length primaries and secondaries now that I've hacked at this for a while. The secondaries really make it trickier. Going shorter than 500mm is also pretty tricky, but probably doable with some time and effort.

[George Hill]

This is one of those projects that sound great but in reality we would all need to see side by side dyno comparisons to even justify it.

I would expect if that is your metric for this project then its probably not going to be something you switch too. There are so many variables in regards to exhaust and what they deliver that just a total hp curve vs V1s or whatever is going to be hard to blow them out of the water.

I'm installing the Kromers for no other reason than I like the way they sound. They absolutely lose torque over stock manifolds and don't pick up a ton over V1s (if any). They don't fit well and are very custom. So my interest is very much different than yours and that is ok, no shade as the kids say.

I'm really enjoying this project as a thought exercise and seeing these guys smarter than myself work through it. If a commercial product materializes that works for my setup, even better. If not, I hope they achieve their goals and maybe that knowledge will be something I can recall back upon in the future.

[oceansize]

When dudes drop $8 to$10k (or more) on wheels, a set of maybe somewhat expensive headers will be alright 🤣

But wait, we can't see the headers.. man... I'm out.

[3staxontheradio]

I'll join you in this if they prove to do what we hope they do.

I'm just skeptical is all.

Very curious what these would cost to produce once finalized/optimized.

If you are willing to split these up into a few pieces to keep the total print size down, then weld them together, the cost should pretty affordable. Less than any of existing high end options. I'm guessing it will be about $1500 based on the test parts I have put into craftcloud.

Careful A/B testing and gathering real data is super important. I honestly do not know why people assume the supersprint V1s are good? and it seems nobody holds them to that standard or any standard other than it being forum wisdom. The measurements are all over the place and they are built to be cost optimized for mass production using CNC bends and formed merges. They charge $$$$ for them. On paper that's not functionally much better build quality than my megan racing headers. Hard pass for the price.

[3staxontheradio]

Here's 500mm equal length (+/-0.5mm) stepped headers - single step from 40mm OD to 45mm OD. Secondaries are also equal length +/-0.1mm and have 100mm of straight section for a merge collector. There's even a straight shot to install every fastener except one. And enough clearance to the frame rail to get the headers over the studs for install in situ.

I'm not sure packaging the bigger OD is going to be achievable with equal length primaries and secondaries now that I've hacked at this for a while. The secondaries really make it trickier. Going shorter than 500mm is also pretty tricky, but probably doable with some time and effort.

That looks great. I can check that in the E36 chassis as well if you want.

I roughed out a quick 15 degree merge with a choke and a reverse megaphone and its pretty challenging to fit. Just a thing to keep in mind:

[Bry5on]

That looks great. I can check that in the E36 chassis as well if you want.

I roughed out a quick 15 degree merge with a choke and a reverse megaphone and its pretty challenging to fit. Just a thing to keep in mind:

Yep that makes total sense. The megaphone doesn’t need to be straight though 3D printing for the win here.

edit: check your email for files. Let me know if you need an export

[Sharocks]

If you are willing to split these up into a few pieces to keep the total print size down, then weld them together, the cost should pretty affordable. Less than any of existing high end options. I'm guessing it will be about $1500 based on the test parts I have put into craftcloud.

Careful A/B testing and gathering real data is super important. I honestly do not know why people assume the supersprint V1s are good? and it seems nobody holds them to that standard or any standard other than it being forum wisdom. The measurements are all over the place and they are built to be cost optimized for mass production using CNC bends and formed merges. They charge $$$$ for them. On paper that's not functionally much better build quality than my megan racing headers. Hard pass for the price.

For under 2k, this would be ideal.

I'm not a fan of the V1's either, they just worked for my cammed car better than the other options at the time.

I also paid significantly less for them during a Black Friday sale on ECS years ago.

Supersprint welds make me believe that the Italians definitely work 5 hours a day.

Also I don't think V1's ever claimed to be equal length, or at the very least i didn't know that they weren't but I wasn't looking for that anyways.

Needed more flow, got more flow, car makes more power (lol) and sounds actually quieter not better.

[0-60motorsports]

For under 2k, this would be ideal.

I'm not a fan of the V1's either, they just worked for my cammed car better than the other options at the time.

I also paid significantly less for them during a Black Friday sale on ECS years ago.

Supersprint welds make me believe that the Italians definitely work 5 hours a day.

Also I don't think V1's ever claimed to be equal length, or at the very least i didn't know that they weren't but I wasn't looking for that anyways.

Needed more flow, got more flow, car makes more power (lol) and sounds actually quieter not better.

Hopefully the price of these new headers, if they make it to production, will be reasonable. If not we rock on with the V1s.

[Bry5on]

Started work on a collector design that takes full advantage of 3D printing last night (constant cross sectional area in a smaller package). Still more work to do as I'm not happy with the runner layout and 3staxontheradio found some bell housing interference but we're making steady progress:

[3staxontheradio]

George Hill Do you have any good kromer kraft s54 sound clips on the street or where there aren't other car sounds?

[3staxontheradio]

Bry5on and ApexPothole
I added the E36 with s54 scan file to the github

https://github.com/AlecMoody/AlecMoody_BMW/tree/main/E36M3

Edit: I also added the scans for the Manzo and Megan headers so now the github has all of these headers on it:

[George Hill]

3staxontheradio

On the dyno, but you can't really hear it.

At the track, but there is some background noise.

[3staxontheradio]

Which stainless Bros muffler do you have?