fuel pump pressure

[nlreb54]

Does anyone know the fuel pressure for a stock fuel pump on a 74 small block? I am thinking about changing the stock pump out with an eldebrock fuel pump to match the carb. :confused

Thanks!

 

[Chas]

i would look at Edelbrock for the pressure you need for the specific carb. i have a performer and have a regulator to 6lbs of pressure....could cause damage if running it over 6 .
my 2 cents.....Chas

Does anyone know the fuel pressure for a stock fuel pump on a 74 small block? I am thinking about changing the stock pump out with an eldebrock fuel pump to match the carb. :confused

Thanks!

 

[81 Corvette]

I've got a fuel pressure gauge and it runs a prettly low pressure. Ussally its somewhere between the 3 and 5 lbs. Stock pump, demon carb, no problems with fuel delivery

 

[72Mako]

Might check your type of fuel pump. On my '72, the stock fuel pump is a 3 port. In/out and return. On mine there is a small return line back to the gastank. Some people have just blocked it off but I prefer to run a return line as I think it keeps the fuel cooler/percolation issues etc. I don't know if by '74 they had gone to a 2 port or not. The stock pump seems to handle my modified smallblock/Holley combo up to 130+ mph. If they ever come out with a hi-po 3 port fuel pump, I'd be interested though. Charles

 

[nlreb54]

I am running a 1406 edelbrock carb now and the carb manual states it needs 6 psi. What would be the purpose of blocking the return line on the pump?

 

[1979toy]

I have a stock fuel pump on my 406. The remote fuel pressure gage reads 5 PSI at idle and 6 PSI at anything above idle, the only exception being that at the end of a 1/4 mile run at the drag strip it's down to 4 PSI. Guess the Speed Demon likes a lot of gas on the top end.

 

[72Mako]

Every hi-po fuel pump I have seen for a small block '72 has 2 ports. Matter of fact, I've got a Carter hi-po new in the box which I had planned on running with my modified smallblock until I ran into the return line issue. If you run a hi-po 2 port fuel pump, you have to plug the return line or be very creative. Like I said if somebody makes a hi-po 3 port fuel pump, I'd be interested. Charles

 

[Vettehead Mikey]

I just gotta ask- WTF will a hi-po fuel pump do for you? If a pump fills the carb bowls fast enough to avoid starvation, any extra capacity/pressure/flow will either need to be bled off, or will cause the carb to flood by forcing the float needle off it's seat.

The stock GM pumps will deliver far more flow than any street engine can use, so why bother?

I also don't understand why you guys install carbs that can't deal with the pressure from a stock pump, and then need to find an aftermarket 'low pressure' pump or put in a regulator to drop the pressure.

:confused

 

[Stallion]

A stock carb for your Vette wouldn't require much pressure at all. The QJet can operate on a minimum of 2 or 3 lbs. Definitely nothing at or above 5. That is too much.

 

[JohnZ]

The stock fuel pump will work just fine, unless you're modified to over 600hp; you don't need a "hot-rod" fuel pump - won't make any difference at all. L-88's ran just fine at 6500rpm with plain ordinary stock AC fuel pumps and stock 3/8" fuel lines. The Edelbrock carb doesn't "require" 6 psi, that's the max it can handle without unseating the inlet needle.

 

[Robin7TFour]

john, would that unseating occur at idle speeds? my carb works great ,except when warmed up and sitting in traffic. it will be fine,then all of sudden an couple of burbles and the die. restarts quickly with just a puff of smoke(black).
i am running a edelbrock #1406(600cfm) with a stock pump,which i checked,runs at 7psi.
i have talked to several CAC'r some have a regulator and some don't. very confusing.

thanks
robin

 

[Chas]

my story...

my situation is that i bought the car with a holley carb.......leaky...and what would seem to be a holley pump....i have no idea what landfill the guy put the factory pump in....So , i had to replace the carb... i went to an Edelbrock carb to match the Edelbrock manifold.... now what do i do? i have a pump that puts out 8 to 10 lbs and only need 6 max....i could always buy an Edelbrock pump...but i think the pump is working fine for now...so i save about $50-$60 by just installing a regulator...now i know for sure the pressure i have isnt going to do anyharm...i would guess that someday i will get the Edelbrock pump , but even then i would leave my regulator on it...just for added insurance.i hope this helps you to understand , atleast from my point.
Chas

I just gotta ask- WTF will a hi-po fuel pump do for you? If a pump fills the carb bowls fast enough to avoid starvation, any extra capacity/pressure/flow will either need to be bled off, or will cause the carb to flood by forcing the float needle off it's seat.

The stock GM pumps will deliver far more flow than any street engine can use, so why bother?

I also don't understand why you guys install carbs that can't deal with the pressure from a stock pump, and then need to find an aftermarket 'low pressure' pump or put in a regulator to drop the pressure.

:confused

 

[nlreb54]

I dont guess I stated my question correctly. I need to know if the stock fuel pump delivers more than 6 psi of pressure?

 

[Vettehead Mikey]

I dont guess I stated my question correctly. I need to know if the stock fuel pump delivers more than 6 psi of pressure?

scroll back up to the second reply to your orignal request.

The answer is no.

 

[Tom73]

I dont guess I stated my question correctly. I need to know if the stock fuel pump delivers more than 6 psi of pressure?

I would assume that the 74 would be the same as a 73. The stock pump on the 73, the factory stats shows the p[font=Arial,Helvetica]ressure range (shut off pressure at 1800 rpm) as being [font=Arial,Helvetica]7.50 - 9.00 PSI at pump outlet.[/font][/font]
[font=Arial,Helvetica][/font]
[font=Arial,Helvetica]tom...[/font]

 

[GerryLP]

I would assume that the 74 would be the same as a 73. The stock pump on the 73, the factory stats shows the p[font=Arial,Helvetica]ressure range (shut off pressure at 1800 rpm) as being [font=Arial,Helvetica]7.50 - 9.00 PSI at pump outlet.[/font][/font]

[font=Arial,Helvetica]tom...[/font]

The L81 restoration package from Chevrolet says the same thing....