S54 Header Design talk

[Casa de Mesa]

Just seeing this thread for the first time. Amazing stuff.

Threads like this make me wish I went the engineering path at an engineering school rather than the business path at an engineering school.

[George Hill]

Just saw this on FB

[Ryan_R]

If you're interested, I can take measurements of my headers. 2.5" collectors made by a reputable exhaust manifold fabricator.

[Sethlayne]

If you can get me the flange measurement that would be great

[Sethlayne]

This is very basic question but I cant download these files

[3staxontheradio]

Some progress is happening again. I have been really busy with work but I just finished pulling my headers to get a scan of the packaging space. This is the last step before I can start laying out some design ideas.




My list of things to look into:

*Steps vs taper vs straight primaries.

*Merge design to maximize effects between primaries. taper/venturi design and how primaries are angled and positioned relative to each other, etc.

*Multiple ways to add anti-reversion geometry. I'm curious about trying something like many small features that eat away at pressure waves little bits at a time (the extreme version of this idea would be something like scales layed close to flat vs bigger simpler anti reversion chambers. Steady state flow testing could at least give good information on what the cost of adding anti-reversion features would be. How effective it is at eating pressure waves going the wrong way would be harder to test or model.

*Non circular profiles in bends and bends that don't follow a simple center line radius for ID/OD. Basically try to open up the CSA or the flow path on the constrained inside edge.




I also just picked up a huge 500mm bed 3d printer (Ratrig VC4) and I plan to use that to FDM test parts and can also use them for some static flow testing.




Lastly, I'm replacing these Manzo headers with a set of Megan Racing headers and converting back to stock flanges for the exhaust to header joint. I'm going to scan the Megan Racing headers and A/B compare them to the bank of CSL headers I scanned so people can get a once and for all comparison of how close in design they are.

[3staxontheradio]

This is very basic question but I cant download these files

There should be a download button when you navigate to a file in the github repo. Its kind of clunky to use.

[siamkazi]

Some progress is happening again. I have been really busy with work but I just finished pulling my headers to get a scan of the packaging space. This is the last step before I can start laying out some design ideas.




My list of things to look into:

*Steps vs taper vs straight primaries.

*Merge design to maximize effects between primaries. taper/venturi design and how primaries are angled and positioned relative to each other, etc.

*Multiple ways to add anti-reversion geometry. I'm curious about trying something like many small features that eat away at pressure waves little bits at a time (the extreme version of this idea would be something like scales layed close to flat vs bigger simpler anti reversion chambers. Steady state flow testing could at least give good information on what the cost of adding anti-reversion features would be. How effective it is at eating pressure waves going the wrong way would be harder to test or model.

*Non circular profiles in bends and bends that don't follow a simple center line radius for ID/OD. Basically try to open up the CSA or the flow path on the constrained inside edge.




I also just picked up a huge 500mm bed 3d printer (Ratrig VC4) and I plan to use that to FDM test parts and can also use them for some static flow testing.




Lastly, I'm replacing these Manzo headers with a set of Megan Racing headers and converting back to stock flanges for the exhaust to header joint. I'm going to scan the Megan Racing headers and A/B compare them to the bank of CSL headers I scanned so people can get a once and for all comparison of how close in design they are.

this is cool, I was wondering what happened to this thread and outcome, awesome to see your work

[3staxontheradio]

Got my Megan headers and scanned them. Loaded up the CSL header scan for a comparison. The main dimensions are really similar. The biggest functional difference looks like the quality of the merge. The primaries are a little different and in a few spots the megans form a corner instead of a smooth radius (bend cut off axis). Overall though for the cost difference I think someone looking for euro headers and not wanting to pay the stupid prices would be pretty happy with these. I never mounted the CSL headers on the cylinder head but the megan's aren't perfectly lined up. The holes for the studs are big enough to take up the misalignment (barely) but I don't think the ports are actually aligned well with the opening of the primaries. That could be another measurable performance difference. I plan heat and hammer mine until they are before I install them.


Manzo header scan is processing now. They look like a copy of the supersprint non stepped headers but with the worst quality formed merges I have seen.


CSL header is in red.





Also I have been looking at different 11mm wrench tools, what fits close to the primary and what can actually be used for service with the engine in the chassis. I pulled the manzo headers 90% with a basic combo wrench (non ratcheting, no room for the gear wrenches) and some with a stubby 1/4" drive ratchet and socket. I ordered a small collection of universal sockets and small tools to measure out and make sure something can install each flange nut. The CSL/Megan headers both have some kind of thin flange with recessed hole for the nut and that totally rules out being able to use a basic combination wrench.the thicker flat flanges like on the manzo headers seem preferable to me.

[3staxontheradio]

Manzo header scan:

[3staxontheradio]

This is CSL bank 2, Kromer Kraft, Manzo, and Megan Racing all overlaid together. Looks like it could make some noise. I'm working on getting all of them fully measured out (OD, ID of each segment and all of the primary lengths and step locations).

[Cronenberged]

This is CSL bank 2, Kromer Kraft, Manzo, and Megan Racing all overlaid together. Looks like it could make some noise. I'm working on getting all of them fully measured out (OD, ID of each segment and all of the primary lengths and step locations).

Would be cool if would could get the PTG headers from the ALMS race car in here.

[3staxontheradio]

If anyone wants to mail them to me I would be happy to scan them.

[3staxontheradio]

Measured out the Kromer Kraft headers and also messing around with different design variations using their layout as a starting point. Just sketches, maybe not the direction I will go in but I do like that the merges are inline with each other so it ought to sound pretty good without needing some complicated section 1. I still need to the full engine bay/packaging scan. Hopefully I can get to that this week. Also I think a design this twisted up and bulky will need individual primaries that slip fit into a merge so they can be installed one by one. I doubt this can be moved in and out of the engine bay as two whole units.

[George Hill]

Keep in mind these KK's are E36 fitment, they do NOT fit an E46 without modification. Specifically the engine support arm, which is easy, but #4 primary is into the drug bin structure, I had to clearance the chassis right there. They will also not work with the factory A/C lines. When I reinstall them I am going to pull the whole front end off the car so I have access on (3) sides.

I do like that the merges are inline with each other so it ought to sound pretty good

Why do all of this? Because they DO sound really good. I am going to test the original 'Y' pipe and and a more traditional dual pipe setup but if the dual kills the sound I'm going back to the 'Y' even at the detriment of the torque curve which is big.

https://youtu.be/juk-elMFBZY