fuel pump questions

[trudysduster]

what kind of fuel pressure and gph should the fuel pump be on a 440. I put one on from a local parts house and wondering if it is strong enough causing my problem. I was told I may have a low compression misfire. thanks

 

[trudysduster]

let me ask this question another way. I believe the fuel pump I put on the 440 awhile back has a flow rate of 33gph and a pressure of 7.4 PSI. I bought it from Oreillys for a 76 440 engine. I was looking at a fuel pump from Summit for this 440 and it has a free flow rate of 120 gph and a pressure of 6-9 PSI. I read that if I am not getting enough fuel it may cause it to run lean. Am I getting enough fuel to this car with the pump that is on there now. am I starving the engine. what do I do with the excess fuel if any. It does not have a return line on the car. can someone help me out on this.

 

[EL5DEMON340]

You can take a hose put it in a graduated container, remove the plugs, and crank it for 30 seconds, do some fancy math and see what you get for GPH. If it's weak make sure the tank pickup is ok.

 

[trudysduster]

I know what the gph is for the pump that is on there right now. according to oreillys part # M16216 precision fuel pump it is 33gph. my question was is that enough to supply enough fuel for this modified 440 engine. The one I was looking at from summit CRT-M4845 I believe it is a carter is pumping 120 gph. I think that is a big difference. I don't know.

 

[EL5DEMON340]

Probably more than enough, ideal fuel psi at the carb is 5 to 6.5 psi. What's a low compression misfire?? Usually a week fuel pump will show when floored and at the top of second or third gear it will fall on it's face.

 

[trudysduster]

so what you are saying without saying it is that the stock fuel pump that is flowing at 33gph and 7.4 PSI is enough for my slightly built 440 and I don't need the one flowing 120 gph. Moper told me that he thought I had a low compression misfire. I googled it and that is where it told me somewhere that the cause could be a fuel pump not supplying enough fuel and causing it to run lean.

 

[trudysduster]

I will figure it out. Thanks Demon

 

[furyus2]

The pump should be enough, unless you are running it hard . try plugging the vacuum advance, and test drive.

 

[trudysduster]

ok,thanks

 

[forphorty]

You will never know for sure unless you put a fuel pressure gauge out on the cowl and go for a WOT ride.