Author Topic: 1968 396/325 Stock Fuel pump pressure  (Read 2129 times)

Tinkerr

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1968 396/325 Stock Fuel pump pressure
« on: March 23, 2020, 10:50:01 PM »
Anybody have any real world fuel pump pressure numbers for a stock pump. I had my motor dynoed today and the pump was only carrying 2.5psi. It was a steady 2.5 but only 2.5. We supplemented with the dyno's electric pump and picked up 5-7 hp above 4800rpms. It would indicate they motor wasn't starving, but seems low. Thanks

Mike S

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Re: 1968 396/325 Stock Fuel pump pressure
« Reply #1 on: March 23, 2020, 11:18:08 PM »
 I checked the AMA manual for the Camaro and I see the V-8's (except L78) listed as having a pump pressure of 5.0-6. PSI
67 04B LOS SS/RS L35 Hardtop - Original w/UOIT
67 05B NOR SS/RS L35 Convertible - Restored

Tinkerr

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Re: 1968 396/325 Stock Fuel pump pressure
« Reply #2 on: March 30, 2020, 11:37:51 PM »
Looks like I'm buying a new fuel pump to replace the one that doesn't have any run time on it. Maybe Ethanol impacted it just sitting around. Thanks for your reply Mike

lynnbilodeau

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Re: 1968 396/325 Stock Fuel pump pressure
« Reply #3 on: April 13, 2020, 03:06:43 AM »
Beware that almost every aftermarket fuel pump made recently has too stiff a spring and therefore too much pressure.   Over 7 psi and you are asking for trouble.

Invest in an inline fuel pressure gauge and check it before you run it.    I had three in a row register over 10 psi.

adjudimo

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Re: 1968 396/325 Stock Fuel pump pressure
« Reply #4 on: April 13, 2020, 05:17:47 AM »
The 396/325 I took out of my 67 stayed around 5.5 lb pressure when it was in the Camaro. I have heard others in my area also complain about the newer pumps running high pressure as stated above.