[urq] Fuel Pump surge - still having problems

[Ben Swann]

OK - great, so the solution is to install the later fuel tank. Nyet!

I am going to try to do something with main feed line to open it up a bit - any
suggestions toward optimizing flow to the pump from the original tank?  I'd like to
retain the pre-filter although it does seem to contribute to cavitation, but does not
seem to cause the problem by itself.

Ben

-----Original Message-----
From: Ingo Rautenberg [mailto:ingo.rautenberg at gmail.com] 
Sent: Thursday, April 17, 2008 10:33 AM
To: Steve Eiche
Cc: benswann at verizon.net; urq at audifans.com
Subject: Re: [urq] Fuel Pump surge - still having problems

Yup.  Larger diameter=slower flow.  Smaller diameter=faster flow.   
Same principle as used for traditional na intake manifold design.   
Longer and thinner runners make the engine produce more torque, but  
less horsepower.  Shorter, larger diameter runners allow for more  
HP.  Best of both is the variable manifolds with valving for dual  
runners.  Forgive me, I digress...

On Apr 17, 2008, at 9:56 AM, Steve Eiche wrote:
> FWIW, later ur quattros as well as other Audis with the external pump
> have a larger diameter fuel supply hose from the tank along with  
> larger
> diameter fittings on the tank and pump.  Perhaps this was Audis "fix"
> for the fuel pump noise issue.
>
> Steve
>
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