Fuel delivery volume of the stock pump

[tag]

I'm in the middle of my first engine build. I pulled the 440 out of my Satellite and basically went to town on it. This is how it's coming together:

• Bore 0.030" Over
• Main & Rod Journals 0.010" Under
• KB Flat top pistons with valve reliefs; 10:1
• Cam Lunati 60304 0.513"/0.533", 276°/284°
• Edelbrock Performer RPM Heads
• Edelbrock Performer RPM Intake
• 750 CFM Edelbrock Carburetor
• Mopar Performance High Volume Oil Pump (P4286590)
• Cheap headers
• MSD 8387 ("Ready to run")
• Blaster 2 Coil

My question is basically, am I going to have sufficient volume from my stock/factory fuel pump? The block was original out of an imperial, docile cam (256°, 0.450 lift I *think*), 625 CFM Carburetor...I have no idea how much it flows. Will I have enough fuel pressure?

The thing that made me think of it is looking back over my build sheet, aside from the turned crank and resized rods and unimportant things like valve covers, this is basically the last remaining factory part.

 

[Meep-Meep]

Sounds like a nice build but you don't need the equivalent of Niagara Falls in fuel delivery. The stock 5/16" line will do fine and if you upgrade the fuel pump to the HEMI delivery rate that's all you need. I have a Holley mech pump on my 440 and it works great. Someone is actually reproducing the old Carter pump that was used on 426 HEMI's but I don't know how much it is. Verify and/or adjust the pressure to 7.5 PSI maximum.

 

[tag]

So the stock pump probably won't be quite enough, you're suggesting?

I was looking at the Edelbrock 1723, which is 6 PSI/110 GPH. To get 7.5 PSI, I could use the Holley 12-440-11 which can push 8 PSI. I don't know how to adjust them but I'm sure there is something I can do.

Edelbrock of course suggests their own, and given that the top-end is all Edelbrock, maybe that's a good plan.

 

[darkhorse]

Meep said you will be OK. and you will be.

 

[70rr-brian]

I have a similar build to yours...well, in principle anyway. I have an 850 QF sitting on top using the stock fuel pump with no issues.

 

[tag]

Meep said you will be OK. and you will be.

He said "and if you upgrade the fuel pump to the HEMI delivery rate"; Which wasn't clear to me since I know nothing about the HEMI or even the 440 Pump really. I read that as "more than stock but nothing too fancy".

I guess I'll just finish putting it together and see what happens.

 

[darkhorse]

np sorry if I wasn't exactly paraphrasing clearly. I do believe you should be fine .

 

[Meep-Meep]

Sorry, I should have been more specific. The HEMI delivery rate is still considered stock - for the HEMI - but is an upgrade for the 440 or 383 2 BBL that is found in grandpa's Imperial.

I had an auto parts store replacement pump speced for a run of the mill big block and it produced 2.5 PSI at idle. I drove the car all over the place and it ran fine. I wound it out in second to 6000 RPM and had a WOT pressure reading of about .5-1 PSI and didn't notice any abnormalities. I put on the Holley mech pump and didn't notice one bit of difference in the way the car ran compared to the lower pressure pump. WOT pressure drop wasn't as low as with the OEM spec pump. One thing to consider is all the fuel that fills the bowl of your carb enters through two ~.090" diameter holes called the needle and seat. A pressure drop at WOT is not cause for alarm but only demonstrating that the needles are fully open and the pump is still capable in creating a little back pressure to push the fuel in, even with two gaping holes in the line so to speak.

I suppose it's possible that the OEM spec pump may have been marginal so to err on the side of safety go with the first stage performance pump. What I'm saying is you don't need 1/2" line and two electric pumps for a reasonable street engine.

 

[bigmanjbmopar]

http://www.summitracing.com/parts/SPE-59013/

If you need comfort put one of these in line next to the carb, keeps the demons out of your dreams lol or should I say chevys lmao