# Fuel Pump Pressure 64 Tri Power



## fredm389 (Mar 2, 2019)

Buying a new Fuel Pump. 
Are there any issues with Fuel pump pressure of 8 PSI vs standard 6 PSI for Tri-power for 1964?


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## PontiacJim (Dec 29, 2012)

fredm389 said:


> Buying a new Fuel Pump.
> Are there any issues with Fuel pump pressure of 8 PSI vs standard 6 PSI for Tri-power for 1964?


Only if the carb floods over and catches the engine on fire and burns the car down.

This has been covered a number of times here. Use the Google custom search feature in the upper right corner and you will find a number of discussions on the subject. :thumbsup:


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## cij911 (Oct 25, 2017)

fredm389 said:


> Buying a new Fuel Pump.
> Are there any issues with Fuel pump pressure of 8 PSI vs standard 6 PSI for Tri-power for 1964?


Yes you don't want to use 8 psi or even 6 psi (the original pumps were not a constant 6 psi). If you get the 8 psi mechanical pump, just buy a regulator and set it to 4 psi and you should be fine.


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## PontiacJim (Dec 29, 2012)

cij911 said:


> Yes you don't want to use 8 psi or even 6 psi (the original pumps were not a constant 6 psi). If you get the 8 psi mechanical pump, just buy a regulator and set it to 4 psi and you should be fine.


Factory fuel pump is rated as 5-6 1/2 PSI @ 1000 RPM's.

With AC, and probably due to the loss of pressure from the return line, 3-5 1/2 PSI @ 1000 RPM's

Flow volume is measured as 1 Pint in 30 seconds @ idle.

:thumbsup:


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## Lemans guy (Oct 14, 2014)

Smart advice,...I run an electric fuel pump gauge in the cab,....really let’s you see what is going on. I am using an edelbrock fuel pump that is 6 PSI. I got tat specifically because it has a strong casting, I don’t need a regulator....but I do run a return line to the fuel tank from the carburetor. 

That return line has an 060 orifice that keeps fuel cool up to the carb and always moving. That with idle drops the pressure to 5 1/2 at idle.

At 75 mph 2500 RPM’s steady 5 PSI,....PSI does properly drop some when a little more throttle is given at lower RPM’s 4 maybe.

Pressure is resistance to flow,....so you can watch as you go.

temperature has a small effect on fuel pressure as well, the viscosity of liquids is effected by temperature. So just like your motor oil is thick when cold and thinner when hot,...I have noticed the same on the fuel but much slighter. About 1/2 pound. Cold fuel is 1/2 PSI higher than hot fuel....you can see it on the fuel gauge.

I do wrap my fuel lines with DEI fire sleeve which keeps them cool and helps a lot of ways.

That Edelbrock fuel pump has stong flow works good.:nerd::nerd::nerd:


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