...well I'm building up another high performance daily drive and I found this while searching for parts. I have not tried it but it looks like a fail-proof alternative which can be easily adapted using a SARD FPR adapter(although the thread isn't metric). It's designed for aircraft which seems odd. Below is and email from the designer/manuafacturer.

http://www.matronics.com/fuelchec/dampener.html

Yes, the pulsation dampener should work fine in automobiles. It
works like the air-hammer dampeners common in household water fawcett
installations. It simply relies on the compression characteristics of air.

The pulsation dampener I supply is a 2" round sphere with a 1/2" NPT
thread on one end. In aircraft installations, the bulb must be
mounted pointing upwards in normal flight. Excessive acro will
diminish the effectives of the dampener, but will return to normal
operation after a period of time.

Best regards,

Matt Dralle
Matronics

 

You need to search a little harder.

 

yeah, yeah...I run a Sard type rj fpr, has an internal fpd...

the 1 i linked costs have as much as your Marren, can be easily adapted if u tap your primary and is fail-proof as it has no diaphram...

 

How's the Matronics unit working out for you?