Rising rate Fuel press. reg on forced indution BMW?

["Rob" <motor@xxxxxxxxxxxxx>]

    Is anyone using a "rising rate" fuel pressure regulator on their
Supercharged or Turbocharged BMW's??   This is not to be confused with a
fuel pressure "riser" or other add-on , but rather a fuel pressure regualtor
that increases fuel pressure at more than a 1:1 ratio based on manifold
pressure.

 Any experience with these??   Any comments??  I've *heard* that these can
be hard to tune?

Thanks
Rob
'84 325i/e
'88 944 turbo S
- -Lots of "ex" BMW's!!!

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