BMW S65 valve cover options (mostly inclusive).

It seems like the EPM valve cover still has the design leaving out the mid hump which was a cause for concern on the V1.

While the integrated tubes is great, it now seems like a trade off, 100% factory reproduction with NRW and non integrated tubes or potential for CCV compromises with integrated tubes.

Although Abdul from EPM in another post defends the design saying there are no indications of reduced CCV performance, based on BenFenner’s write up on CCV it seems any reduction in the surface area of the valve cover will change the CCV performance. Since Abdul suggests the only advantage to not having a 100% factory reproduction is aesthetics, it seems like an odd choice, since the valve cover is almost entirely covered when the engine is out together.

100% factory reproduction billet with integrated tubes. Unfortunately it isn’t so.

I think i will still stick with NRWs VCs when I go to do my VANOS covers.

Agreed, it is unfortunate there is no "perfect" solution available so far. People will have to weigh the pros and cons themselves as usual.

The NRW covers now come with a leak-resistant, billet oil filler cap, so I've updated the notes to reflect this.

This question has come up before, so I’d like to provide some additional context and clarify it properly.

First, I genuinely appreciate Ben’s work and the discussion surrounding the different products available. Every product brought to market should be open to fair criticism and technical scrutiny, and I welcome it. These conversations ultimately benefit all of us as owners and push manufacturers to build better products.I’m always open to revising our designs when evidence shows that a change will produce a meaningful improvement. Adding the factory-style hump would actually be very easy for us because our covers are machined from billet.

With that said, Ben raised a theoretical concern. He did not provide testing or evidence showing that our valve covers reduce CCV performance. Ben says “presumably”, his own word, meaning it’s an assumption, not a measurement. We’ve had these on cars for two years with zero reported CCV issues. Real-world results beat a presumption. The “mid hump” concern has never been supported by real-world evidence. Repeating a theoretical concern does not turn it into a proven defect.

The claim that any change in internal surface area automatically compromises the CCV system is an assumption, not a demonstrated engineering conclusion. CCV performance depends on the complete system. Continuous internal path, cross-sectional area, pressure drop, baffling, and drain-back. Not simply whether the cover reproduces every contour of the factory casting.

Our V1 covers have been installed on cars for more than two years and driven for thousands of miles. In that time, we have received zero reports of increased oil consumption, excessive oil entering the intake, abnormal crankcase pressure, smoking, or any other symptom indicating reduced CCV performance.

Our V2 Billet Valve Covers retains the proven internal design while adding fully integrated spark-plug tubes, eliminating additional seals and potential leak points. Calling this a “trade-off” assumes a CCV compromise that nobody has actually demonstrated. If someone produces controlled testing showing otherwise, we will examine it seriously and change our design instantly. Until then, the available real-world evidence supports our design.

Finally, every one of our products goes through independent review by third-party engineering companies, including IPF Racing, Performance Driven Design, RCE Technologies, and others. These are established automotive engineering firms that conduct their own design analysis and testing. If the internal geometry presented any legitimate concern regarding CCV performance, it would have been identified, flagged, and corrected during development. Our final designs are based on collective engineering analysis and real-world validation, not the unsupported opinion of any one individual.

Abdul

Does anyone have images of what it looks like inside the OEM valve covers where that hump is? I'd love to see what is inside.

If not, maybe I'll go cut mine open and post my findings. They are headed for the scrap bin anyway...

Not necessarily a picture. But I looked through my images and found these two videos looking at the inside of the OEM valve cover side by side with V1 and V2.


S65 Valve Covers- Side by Side - Part 2

BenFenner Since you have a ton data on your sheet. I probably would include this information as well. And this good information for the rest of us reading this.

Another observation worth mentioning based on the two videos I posted in my previous post, is how clean the hard-anodized billet covers remain internally compared with both the factory magnesium covers and raw cast-aluminum alternatives. OEM covers commonly show significant oil staining, varnish, and residue buildup, partly because their internal coating deteriorates and becomes rough after years of heat cycling. That uneven surface gives deposits more places to adhere and collect. The OEM valve cover in the video just looks terrible.

Cast-cover manufacturers generally avoid powder coating the interior, which is understandable because powder coating is a separate layer that could eventually deteriorate or flake into the engine. However, that leaves the naturally rough and irregular cast-aluminum surface exposed, potentially giving oil, varnish, and residue more places to accumulate.

EAE/EPM Billet covers use a uniform, hard-anodized internal surface. Unlike powder coating, hard anodizing becomes an integral part of the aluminum rather than forming a separate layer over it. It does not suffer from the same flaking concerns as the factory coating or internal powder coating, while the cleaner machined geometry provides fewer pockets for oil and residue to collect compared to OEM covers or cast covers.

Please note, this alone is not a controlled comparison. The factory covers were on my car longer than the V1 covers but after more than 10k miles real-world use of the V1 covers, the cleanliness of our covers is another encouraging indication that the material, finish, and internal design are working as intended. In fact, the bottom surfaces look like they are brand new.

Abdul

Wait, are you saying the gold covers in that video have 10,000 miles on them? They look new


RE: Photos- as soon as the V2 covers show up, I am going to have them swapped and will keep the OEM ones for photos.

omgzirra_exe wrote

Most aftermarket valve covers that are powder coated tend to cause grounding issues because the coating acts as an insulator. (you actually will have to sand it down to the metal again)

You'd think anodizing wouldn't have the same problem, but it actually does. The anodized layer is aluminum oxide, which is also an electrical insulator.

If EPM is masking the factory grounding points before anodizing, then it shouldn't be an issue. I don't know if they do, though.

Personally, I'd buy them raw and mask off the grounding surfaces before having them coated or anodized if you're set on a color. That way you know the grounds have a clean metal-to-metal contact instead of relying on the coating being thin enough to conduct.

this makes ZERO sense, the ground isnt grounding on the cover at all. Its grounding from the bolt and being sandwiched between two metal parts (the nut and the metal on top of the grommet.)

the valve cover itself is not touching anything metal. it has a rubber insulator/seal between it and the cylinder head and each bolt holding it in has a rubber insulator/seal.

Thumbie wrote

Wait, are you saying the gold covers in that video have 10,000 miles on them? They look new


RE: Photos- as soon as the V2 covers show up, I am going to have them swapped and will keep the OEM ones for photos.

Yes, they have 10k miles on them. They were removed literally a few minutes before I ahot that video.

Abdul wrote

Yes, they have 10k miles on them. They were removed literally a few minutes before I ahot that video.

That's awesome. MY S65 is patiently waiting for them to ship out

saxon wrote

this makes ZERO sense, the ground isnt grounding on the cover at all.

There are two coil harness grounds. One of them does connect to one of the valve covers. It is below one of the coil cover riser mounts. Or coil beauty cover stand-off pylons. Or whatever you want to call them.

saxon wrote

The valve cover itself is not touching anything metal. it has a rubber insulator/seal between it and the cylinder head and each bolt holding it in has a rubber insulator/seal.

Yes, this is correct. But it doesn't mean that you can't "ground" to it. Even if the valve cover doesn't connect to the negative battery terminal (worst case scenario), it is still a large electron source and works as a capacitor of sorts in this instance.