Fuel pumps

[BillOhio]

I was wondering, do the numbers on ac fuel pumps such as 40669, mean it is just for a z, or do some of these pumps have different flow rates? I doubt if I find a 40669 but have seen correct appearing ac logo pumps and curious if they have different GPH ratings  if they take the same size fuel lines

[janobyte]

That's a good question, I approached it last year with no luck. Was looking for the GPM on a stock/replacement pump.

[JohnZ]

That's a good question, I approached it last year with no luck. Was looking for the GPM on a stock/replacement pump.

You won't find a GPM rating chart - the number on the pump is primarily for the pump configuration, essentially the bottom half; where are the inlet and outlet, which way do they point, are they clamped or threaded joints, etc. Shop Manual calls for the same volume for the same time for all pumps.

[69Z28-RS]

That's a good question, I approached it last year with no luck. Was looking for the GPM on a stock/replacement pump.

You won't find a GPM rating chart - the number on the pump is primarily for the pump configuration, essentially the bottom half; where are the inlet and outlet, which way do they point, are they clamped or threaded joints, etc. Shop Manual calls for the same volume for the same time for all pumps.

John:  You said 'primarily' for configuration; Does that mean that if there's a PN difference, that there's some difference in the I/O configuration alignment, orientation, or fitting size/type?  OR is there something else to know about this?   

[Steve Shauger]

That's a good question, I approached it last year with no luck. Was looking for the GPM on a stock/replacement pump.

You won't find a GPM rating chart - the number on the pump is primarily for the pump configuration, essentially the bottom half; where are the inlet and outlet, which way do they point, are they clamped or threaded joints, etc. Shop Manual calls for the same volume for the same time for all pumps.

John:  You said 'primarily' for configuration; Does that mean that if there's a PN difference, that there's some difference in the I/O configuration alignment, orientation, or fitting size/type?  OR is there something else to know about this?   

There are many instances where externally pumps are configured identical but have different part#'s (built in same time period). Therefore I believe internally, output (volume/pressure) was also a reason for different part#'s.

[Gramps69Z]

Volume is the same for all engines.  Pressure changes from six cylinder, small block and big block.  The input and output fittings will be different from engine to engine as stated.

[janobyte]

1 pint in 30-45 seconds across the board per 68 Overhaul Manual.  Average 37.5 seconds per pint=96 pints/hr.=12 GPH.  (.125 multiplier) roughly 2lbs. of fuel

     5-6.5 psi fuel pressure : 302-350, 290 hp-350 hp.

   (demand@ WOT)=(.5 lbs. of fuel per hour)HP ex: 290 hp x .5 = 145 Lbs/hr = 24.17 gph.  I however do not think many here are racing their vintage 302's at WOT for an hour ! Stock pump for stock driving probably fit the bill, engineers had it figured.

Now Bill, what do you think your Plymouth sucks down in a pass ? 2625#'s (car + driver) , 670hp (flywheel) 413 sbc will eat up around a half gallon between idling to staging-burnout-run-idling to trailer. Apples and oranges.

[BillOhio]

I have not raced it but know its probably getting under 10 mpg. Gauge acts funny so I top it off regularly. 1300 cfm with one to one linkage and a fair sized fuel pump. Of course there's no way to drive it kindly.

[BillOhio]

I checked and the mechanical pump on the hemi flows 110 GPH. I might put my pump on that replaced the 40669 and hope it doesn't leak. It has the correct logo but wrong number. I think its 40 years old and might see what the repops look like