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Re: [T3] Fuel Pump Specs

On Mon, 2005-02-14 at 15:14, James Montebello wrote:
> Pumps don't deliver "pressure", they deliver "flow". 
> A  restriction in the line after the pump (like the
> fuel pressure regulator) is what makes "pressure". 
> The pump merely has to be able to pump fuel against
> that pressure to operate.  Increasing the flow w/o
> touching the FPR will increase line pressure. 
> Twisting the adjustment bolt on the FPR will alter
> line pressure w/o altering pump flow.  So, the two are
> related, but can be adjusted independently, so you
> can't really get pump flow from the pressure w/o
> knowing the restrictions.
This is not entirely true. Some fuel systems are "returnless" systems.
The pressure is regulated right at the pump, and it maintains a constant
pressure in the fuel rail at the engine. The regulator senses the flow
and adjusts the pressure in response to demand. There is not regulator
on the downstream side of the engine.
Bosch builds one of these systems for the JEEP, and the SeaDoo Jet Skis
Walbro/TI builds them for Chrysler/Daimler, and Mercedes.
There is one on Saturn, and some of the Ford Trucks, and now we are
building the regulators for one of the GM products. I don't know which
We sell to Federal Mogul and many countries overseas.

> SOME pumps are internally regulated to a certain
> outlet pressure, but I don't believe this is true of
> the Bosch rotary pump.
What you are refering to are the pumps with internal relief valve. Our
pump is one of those. That is what the third line is for. Ours is
approx. 60 psi.

Russ Wolfe
'71 FB AT
'66 FB MT
'64 T34 (not running)
'65 T1 (not running)

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