I am ordering a new fuel pump for my TPI motor. Is the stock GM in-tank fuel pump capable of putting out 50 psi of fuel pressure? What is the highest it can put out? Any help is greatly appreciated. Thanks.

 

Yes,it will.
However like any pump, the higher the working pressure (PSI), the lower the pumped volume (GPH or LPH). Also the pump will run hotter, heating the fuel and reducing pump life. Why not go for a Walbro performance piece? They are cheap, reliable and availabe in an assortment of flow ratings.

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Tracy /AKA IROCKZ4me
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I think its rated at 50 PSI.

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1991 Camaro Z28
5.7L 5-Speed (originally 305)
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Are all the multiport fuel pumps the same? Like the 2.8, 305 and 350 tpi?

 

How will the pump run hotter? All you are doing by adjusting the pressure is changing the amount of fuel being let into the injectors. It's not like the computer or anything makes the pump work harder. Am I right or am I mistaken? Thanks for the input.

 

Yes, more pressure = more pump heat.
The higher the working pressure of the pump, the more load against the pump impeller. The more load against the impeller (head pressure) the more electrical current the electric motor spinning the impeller draws. The voltage stays the same (as long as there is no drop do to a bad battery or alternator, and no bad connections or wire that is too small).
Wattage is a product of current and voltage (Volts X Amps = Watts). Wattage is a measure of heat. When voltage stays the same and current increases, then watts (heat) increases.
Your right about the computer, it doesn't do anything that would increase pump heat. It just applies a voltage to the fuel pump relay to turn on/off the pump.


[This message has been edited by IROCKZ4me (edited May 20, 2001).]

 

As pointed out earlier, why not get a Walbro high volume pump? It can handle the higher pressure with minimum heat transfer and only costs about $100 from most vendors.
I run a Walbro 307 in my GN and it hits 65 psi easy on those 20# turbo boost blasts!
You can get an even bigger one, the 340 which is a 307 that has been shimmed.

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Rob
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