Charlie Moua
2026-04-17T09:13:31-05:00

DoryokuMFG - The BEST Valve Covers in the Game.
Let us tell you why.
We liked to believe that we were 99% of the way to a perfect valve cover. In fact, we were.
That last 1% was the one thing that scared everyone away from achieving perfection. It was too involved, too
much work, too much time, and too much money.
Not too long ago, we were practically doing the same thing that every other (good) coating company was
doing.
Masking grommet surfaces, blocking off entrances to the baffle, hot tanking, multiple washes, pressurized
air; Literally everything you could possibly do to ensure the best product possible. The result?
A valve cover that was as clean as it could be, but always left us wanting a little bit more.
We did our due diligence to ensure the cleanest covers, but…
There were two words that always kept us up at night. What if?
What if oil seeps through that pitted grommet surface?
What if the masking of those surfaces could look less like a 2 year old trying to color within the lines?
What if contaminants were still behind the baffle?
What if those contaminants make their way to the bearings?
These two words haunted us so much that we decided to do something about it and traversed down a path
that no one has ever dared to.
We invested in custom tooling for CNC machining, spent countless hours in setup design, damaged multiple
valve covers, and then damaged even more covers.
We got to a point where we asked ourselves if this was even worth it.
All to achieve that last remaining 1%.
It was difficult, but we wanted perfection.
Say goodbye to those sloppy masking lines and pitted grommet seats. These valve covers are getting older
and older after all.
Custom tooling was made to take off just enough material to restore a perfect sealing surface while also
producing precision “masking” lines.
And it gets even better.
That fear of contaminants existing behind the baffle? No more.
Additional custom tooling and holding fixtures were made to secure the valve cover in order to precision drill
the OEM rivets to remove the baffle.
We’ve seen baffles in brand new covers that have already begun oxidizing from just sitting in storage.
So what extra step did we take?
The baffle would then be blasted, cleaned, and zinc coated for additional corrosion resistance.
This also adds some nice “bling”, too. Who doesn’t love that?
The chamber behind the baffle is blasted and cleaned too.
The remaining holes from drilling would then be CNC tapped in order to re-secure the baffle with fresh, high
quality stainless steel, flanged (T25) M5 Torx fasteners.
We’ve seen this process done by hand and it’s never a pretty sight.
The holes are all different depths.
The threads are crooked.
Thread engagement is sloppy.
The CNC process that we use ensures superior thread engagement.
It’s honestly satisfying.
Why go to these lengths if a majority of the time, these valve covers with OE baffles don’t have any issues
after coating?
You’d be very surprised.
We’ve received freshly coated covers (by other companies) from customers for the baffle service.
Want to know what we found?
Even after extensive cleaning from the coater, and honestly to no fault of their own, we still found concerning
amounts of contaminants and media hiding behind the baffle.
Might as well “Salt Bae” a pinch of sand into the oil fill at this point.
This further confirmed that we were doing the right thing.
The amount of time, money, and work invested was worth it.
It IS worth it.
Moving forward…
Want to coat your cover another color? Cool. Remove the baffle and clean out the media.
Blew up your engine? Cool. Remove the baffle to clean out traces of your rotating assembly.
Need to drill into your cover to add fittings? Cool. Remove the baffle to clean out the shavings.
You can now rest easy, no longer having to ask… What if?
Now we know, with 100% certainty, that the cover is clean.
We love what we do.
We’re car guys just like you and are so excited to be able to offer these services.
There’s good, better, and best.
It’s clear what this is.
It’s the best.

It’s the perfect valve cover.

Key features:
● Powder Coating
○ Durable and chemical resistant coating
○ Superior corrosion protection
○ Stunning color options
● CNC machined grommet and M6 surfaces
○ Removes pitted and uneven surfaces
○ Provides a perfect sealing surface for rubber grommets
○ Doubles as “precision masking” of grommet surfaces for the cleanest look
● CNC modified serviceable baffle
○ CNC drilled and tapped holes for proper thread engagement
○ Zinc plated baffle for added corrosion resistance
○ High quality stainless steel, flanged (T25) Torx M5 fasteners w/ locking washers
○ Comes uninstalled so customer can ensure proper installation and verify cleanliness for
themselves
● Optional fabrication requests
○ Bungs/fittings, shaving, cutting/notching
● S2000/F-Series Specific
○ OEM baffle removed and replaced with a custom laser cut and zinc coated, stainless steel
baffle
■ Superior drain-back provisions
■ Eliminates oil from entering the vent tube and PCV
■ Eliminates oil consumption and the clouds of burning oil while cornering
■ Eliminates overflowing catch cans
● H-Series Specific
○ OEM baffle removed and replaced with a custom laser cut and zinc coated, stainless steel
baffle