Fuel pressure question

[SS Shaun]

Ok so I finally got around to install a new fuel pressure gauge. I also installed a new fuel filter so when I went to check for leaks I had my wife start the car for me saw no leaks looked at my gauge and I noticed the fuel pressure was sitting at 3.5 psi. Revved it up and it went to 5 psi. Is this normal? I always thought 7 psi was the magic number

[shadowgray396]

Mine at idle is around 3 psi and at 1100 to 1500 rpm goes up to 5 psi.

Stock mechanical fuel pressure is usually somewhere around 5 PSI, maybe 7 on a real strong pump. Above 7 PSI and most common automotive carbs will start blowing the needle off the seat.

[mestorod70]

7 psi is the MAX for a carb setup.
If its a factory mech pump your in the ballpark.
If you think your running out of fuel on the top end. then an aftermarket
mech pump will get you more psi.
I run my holley electric pump at 6.5 psi.

[SS Shaun]

Ok I wasn't sure I mean mine runs fine. I have never gone above 4500rpms so I guess I am good. I just wasn't sure. Around 2000 rpms I noticed it was at 5psi but if it's in the range I am ok then thank you

[chevymaher]

Yes 5-7 is the range and carbs do begin to flood after 7.

[SS Shaun]

thank you for the info. I was just wondering i thought 3 psi was way to low. I guess i am so use to EFI with 42-60 being the norm...lol

[chevymaher]

I am old I grew up with, and prefer carbs.
All you got to do is get the quantity of gas to the bowl. In a carb vacuum literally sucks it out the jets.
EFI it needs pressure to force it out of the injector. So it will spray and produce a mist.