Kevin in Atlanta

I've spent a lot of time thinking about how to design a better approach to manufacturing our regulators and dampers.

I've had Bosch ones dissected - I posted the results in another thread.

I recognized what made them the same and different. I am a software programmer in heart and practice and I tend take large code and create smaller reusable modules.

It became clear that with a single body and cap and purpose specific inserts I could build plug and play regulators and dampers for all years.

Here's my design in 3D:

The FPR/FPD Family

FPR or Front FPD - depending on the insert

Rear FPD

I have completed all the engineering and next up are working prototypes.

Spring rate and preload have been calculated for 85-95 FPR and FPDs.

The cap will be shorter once the springs are selected.

My vacuum reference is 90dg to the cap. Allows a smaller form factor.

Trying to get to the same size as the Bosch units.

Comments welcome.

GregBBRD

Looks just like mine, minus some learning curve stuff.
How about making something unique, instead of just duplicating what I already make?

Kevin in Atlanta

You have designed and produced some of the most amazing pieces for our cars. I am glad to have them on most of my cars.

And you don't get enough credit for all the free advice you give so willingly.

Greg, I hope we will always be friends in competition.

Kevin

khalloudy

Personally don’t like the bolts. How about you make the top part twistable into the lower part and that way you have a clean looking module?

P.S. speaking of engineering, I am so OCD that I can drive an ant crazy looking at the most minute details

Kevin in Atlanta

Yeah, I tried to do that with the initial design. But you have to overcome the spring preload as you turn the cap - and nobody wants to watch a projectile shoot across the room. :-)

And you would still need a way prevent the cap from unscrewing - and the torsional force of turning the cap could abrade the diaphragm.

So, yes I considered it.

That's why I moved to the cap that overlapped the housing. It gives the appearance of a single piece part and the diaphragm is the better for it.

I am still trying to get my engineer to make the brim of the cap thicker so the screws will be hidden. Wish me luck.

The goal was always to get a product that was very close to the Bosch. And from the side I got pretty close.

Thanks for your input.

GregBBRD

The "market" is so tiny....
And there are so many things that the 928 community needs....
Why build something that is virtually exactly what I build?

Kevin in Atlanta

Please understand that what I am about to write is lighthearted and I mean no disrespect.

You take every opportunity to take swipes at the rectangular FPDs and FPRs. I have never gotten into a back and forth with you because it serves no purpose.

I have the utmost respect for your talents - unrivaled in my opinion.

But, while you let everybody know the failings of my rectangular bodies I was listening very carefully and taking notes.

Instead of getting upset I used your criticisms to help design the version you see here. I listened to every complaint. I did a lot of research.

Had you not so been so Greg-like I might have never designed this version.

So, as the President of Finland said to Putin - "You only have yourself to blame." :-)

I want state again I have mad love for you and will never take shots at your pieces.

And for the record I have your cam cover oil baffles and a couple of harmonic dampers with your custom piece and oil filler baffle.

I would never go anywhere else. Period.

I would never dream of copying, ala Potdog, your work.

But, if I can offer a free suggestion about your oil filler baffle - you need to make the snout curved so you don't need to remove the coolant crossover to install it.

I kind of envisioned it with a pivot so it could slide in. I have this affliction - I am always noodling about how make things better. Evil version of OCD.

I can have it designed and 3D printed - give the files to you - I love this community and I like giving back when I can.

I want you to sell more parts - it is a boon to the 928 community when parts that are no longer available or stupid expensive.

These parts fight against the rumors that our cars are too expensive to fix and maintain.

Best, Kevin

PorKen

Very cool!

I like that it looks very much like the stock piece... versus a urinal flush valve like the other guy makes.

911 folks would like this too, I imagine.

GregBBRD

Kevin:
Let's be frank.
You are doing this for your best customer, because I no longer will do business with him, because he is a full on crook.
Wait until he screws you a few times....or doesn't pay you for six months at a time....or flat out copies whatever you have dreamed up.
You'll be singing another tune.

What you have there are copies....with tiny details changed.
Copies of what I already make, which work perfectly.

Have some class and don't just be another person making copies of what I already make.

Bulvot

Thank you for doing this.

Without revealing the secret sauce, how do these compare to the stock pieces:

-FPR: static and idle pressure, LPH supported

-FPD: volume available for damping, pressure range supported

What will be the rebuild process and parts ordering/availability?

Assuming that they meet or exceed stock performance, and you have a version for the early '87 return line connection on the FPR, you can count on me for a full set of the three pieces for a stock '87.

If they exceed the stock pieces enough to compare with the Radium versions, I will take a second set for my turbo charged '87. But, I would need some hard numbers for this application.

Kevin in Atlanta

Target is the stock performance. Great care was taken to match volumes, preload and spring rates.

After the prototypes are completed then I can answer your related questions.

As for the S3 and early 87 applications that boils down to spring rate and a different insert. But, I think using the 87+ housing and a FPR to fuel cooler line like Greg offers is a better solution.

I have this crazy notion about tuning the dampers and regulator to maintain correct pressure on the rails and dial in the dampers to address lean conditions under different loads.

Adjustable dampers? That's just crazy talk, right?

And then what about progressive springs? It could be utter nonsense.

Kevin

GregBBRD

Shocking that you would not support me, regarding Kevin making a copy of what I already build.

Do you suppose he will come up with dampers that work with your complete f^ck-up of when you made your "custom" '85/'86 chips, increased the fuel pressure to '87-'95 specs, and left the stock old dead '85/'86 dampers on the engine?

I make dampers to correct your grievous error, BTW....one of my best sellers.

mb911

I do enjoy reading all these threads. Always some 🔥 conversations.

Kevin will these replace your existing units completely?

Kevin in Atlanta

Thanks for all the responses - mostly offline - seems folks prefer not to get caught up in the back and forth - I appreciate your support.

Lot's of other 928 parts on the drawing board to come.

Kevin

Landseer

Thank you. Help us keep these cars running. That doesnt have to be expensive.