Fuel pump size

[cabledog]

Hello again. So I ordered a fuel pump to replace on my 1971 383 magnum but I double checked and it was only 20 gph with 6 psi max. I cancelled it and ordered one that is 120 gph 6-7 psi max.

Holley said I needed at least 80 gph. Would the 20 gph have worked?

Holley 750
292 cam but otherwise no additional mods

 

[Bill Monk]

I have a carter on the 440+6. I would not take a chance on 20 gpm
https://www.summitracing.com/parts/crt-m6903/overview/make/plymouth

 

[Don Frelier]

I agree with Bill on the Carter that is a great fuel pump.
But a slight correction 20gpm above is a typo. It's 20 gallons per hour or 3 minutes per gallon. So if you get greater than 3 or 4 miles per gallon you are OK just driving. It's wide open throttle that is the question will the bowl level drop after about 5 seconds?

 

[73HEMI_RR_GTX]

I would think that 60-70 would be about right. Your talking about a motor under 450 HP.
Here's a fuel flow chart that may help. Also if your not running at least 3/8 fuel line you probably can not flow more than 60gal/hour.

 

[Larrry B.]

I'm using this one on my motor after changing out the electrical pump.
https://www.summitracing.com/parts/crt-m4862/reviews/

Does a great job on a hot 383.

 

[biomedtechguy]

I switched out to the Carter M6903 on my 440+6bbl as noted above. It delivers appx 6 lbs of pressure and 120 GPH. It is the legendary replacement mechanical fuel pump!