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Old 01-18-2012, 06:20 PM
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gary@germanautosolutions gary@germanautosolutions is offline
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Location: Grand Rapids, Michigan
Join Date: Jul 2010
Posts: 425
Mein Auto: E39 528i, E60 M5
Question: Is the diaphragm robust enough to handle the extra mass of the new flapper and pivot? I wonder if this fix will move the failure point of the DISA valve from the flapper to the diaphragm.
Thanks for asking. If I've missed something, I need people to bring it to my attention so I can address and correct it. If someone has a concern that is a non-issue, I need to be able to respond and clarify why I think so.

1) There is really no mass related load put on the vacuum actuator. The system moves slowly enough that the small rotational inertia difference if insignificant.

2) The vacuum actuator is fully loaded the entire time that the valve is in the closed position, which is most of the time. That aspect doesn't change with the aluminum parts compared to the plastic ones. Since the OEM design has the diaphragm under full vacuum load to keep the valve seated against the molded in silicone rubber gasket, and since that load is many, many times greater than the force required to rotate the valve, it's a non-issue.

What's the kit going to cost?
No definite price yet.... but based on known material costs, current machining time, blasting, anodizing, etc. Expect the complete kit to come in at around $85-$89.

I think I do. Isn't that what #6 is in this diagram:
Yes, that's it. If you have a used bad one I would be happy to pay your packaging and shipping costs.

Once the titanium pin is out I'll snag a kit from you.
Great! Thanks doru. Just for reference, the new parts only weigh 13.5 grams more than the stock plastic valve with steel pin.

Is the 525 version so different? Aren't they both M54 engines only varied by perhaps stroke or bore size? Cost anyway?
I don't know yet what if any differences there are between the 2.5L & 3.0L DISA units. I just know that they have different OEM part numbers. We are all hoping that the 2 parts that matter are the same. If not I will need to make a different flapper for the 2.5L versions. I can't imagine that the bellcrank lever is any different.

"I'm a little rascal on my Little Rascal"
- unknown
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