I always hear how electric fuel pumps are superior to mechanical fuel pumps, which may be true, but is completely opposite from my experience. I understand the push vs. pull of fuel and the constant fuel supply vs. spurts of fuel...so no need to really get into that. I'm more looking for an open minded, unbias explanation as to why electric pumps are supposed to be superior. In my experiences, I've had more flooding issues with supposed properly rated psi electric pumps, where a mechanical performed flawlessly. Most recently, I had a mechanical pump on my 351M and got 10mpg's city and 14mpg's hwy. Then the eccentric went bad...which is a pro for an electric pump obviously. But when I replaced the mechanical with an electric (rated at 4-7 psi), everything performed the same, but my mpg's dropped to 7 city and 10 hwy...a big downfall IMO. Then, in another engine (400), with the exact same electric pump, I got 5mpg's city and 7.5 hwy...and it accentuated the same problems I'm still having with the mechanical pump which gets about 8mpg's city and 10 hwy.


So I guess my current gripe is why the drop in fuel mileage? Is this common across the board? Because these are consistent results I get any time I swap back and forth. And I figure it would make sense considering an electric pump is a constant stream, thusly providing more gas than the spurts of gas from a mechanical. Not to mention the fact, that when an electric pump goes, it's toast...and typically with a mechanical pump, you get a few warning shots first.


So now I'm just gonna sit back and see what you guys have to say and educate myself.

Roof tank= gravity feed,

m78 said:

Roof tank= gravity feed,

Click to expand...

ba ha ha ha ha

Ben, I helped a buddy of mine do a 350 swap into an S10....that S10 fried 3 electric pumps before it left the shop. IMO they don't supply enough fuel in some applications. I also believe that the high flow mechanical pumps are crap and not worth the money...so, stock mechanical FTW.