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Sunbear
03-10-2017, 02:53 AM
I would like to know how many gallons per hour and a psi an electric fuel pump should produce for a carbureted 302 engine, with no high performance parts. I would like to run without a regulator or a return line. Is 35 gph enough, or would it starve the carburetor? Thank you for your help.

CraigS
03-10-2017, 08:02 AM
One of the common specs I often see is 155 litres per hour. So a real rough comparison is 4 L = 1G or 4x35 = 140. I think you will be fine.

Boydster
03-10-2017, 09:07 AM
A carbed engine will only need 4-7 psi depending on the carb. Check with the carb manufacturer for required details.

No Hipo parts... lets assume 200 hp. (200 x .50 BSFC) /6 = 16 gph or 60.5 lph.

With no regulator and no return, make sure you get a pump that is internally regulated to max 7 psi. These are commonly available and not very expensive.

NAZ
03-10-2017, 09:10 AM
Sunbear, you don't provide enough details to calculate exactly how much fuel your engine will consume under WOT but making some assumptions we can get close. Calculating the airflow requirements of a mild 302 @ 6000 RPM with 80% VE and using 13.5:1 best power A/F ratio it looks like the most fuel it would burn is 142 lb / hr. That's ~23 GPH under WOT at 6000 RPM, your average will be much less than that for a street car. So it appears you don't need a very high flowing pump for that little engine if it's just a garden variety SBF with no performance adders.

edwardb
03-10-2017, 09:13 AM
Mechanical fuel pump??? Easier, cheaper, dead reliable. JMHO

cgundermann
03-10-2017, 10:33 AM
Agree with edwardb for a mechanical pump with a carbed motor. Was surprised how loud my external pump is for my EFI motor, so - internal pump is a consideration...