electric vs machanical fuel pump?

[dodgezilla]

I was wondering if anyone has switched from a machanical fuel pump to an electric in line one? I am running a edelbrock performer carb with the offroad kit that puts springs in the needle and seat that are supposed to help when driving on angles. I noticed this last weekend, while wheeling in Moab, that when the truck was point up or down it would not want to idle. If i used both feet to opporate the gas and brakes it wouldn't. My thought is that the machanical pump isn't pumping enough gas to the carb when at idle but does better when reved up.

Any thoughts?

Thanks

 

[Tacoma]

either that or your carb needs tuning

 

[notajeep]

I had this same carb on my blazer way back in the day and never could get it to run on an angle.

 

[Bear T]

My dad is running the Edelbrock 850 on his Bronco with the offroad kit, it does a lot better than any of the other carbs he's ran. Tuning sounds like the first step, its not easy, but you'll know it when you get it dialed in. He is running both mechanical and electric, the mechanical won't feed enough fuel when he gets into the throttle or on an incline. As for myself, I had one of those giant fancy Holley mechanical fuel pumps on my motor, with a Carter 900cfm carb, did fine, till it got on inclines, then the pump died, stuck on an electric and the problems went away. Just my .02

 

[Rot Box]

I have never been a fan of the Edelbrocks offroad even with their "offroad kit". I have always tossed them for a good reman Quadrajet and never looked back. It's all opinion, and thats mine :-\

Anyway on my Toyota I found that with an electric pump I didn't need to crank the engine over to get the fuel to re-prime after stalling on steep inclines. Having gone to a fuel cell I now use a mechanical pump, and really noticed a difference when it came to restarting after flooding out I'll probably go back to an electric one in-line.

Also running a pressure regulator REALLY helps. If you think about it mechanical pumps pressure can vary depending on engine rpm. Gassing it on a steep incline (with mechnical pump and no reg) to get over an obstacle can actually push fuel through the needle and seat with a slight pressure, and cause the bowl to over fill if that made any sense A regulator/electric pump really cuts down on this.

 

[jsudar]

^^^^a fuel pressure regulator is a good idea whether you go electric or big volume mechanical.


As far as carbs go, I really liked my Quadrajet. I spent a lot of time making sure it was rebuilt correctly, but it would run on a pretty steep hill. I would crank the idle up to 900-1000 rpm when wheeling and it would do pretty well.

With that said, I would never ever go back to a carb after wheeling with EFI.

 

[Tacoma]

Quadrajets rock because of the centered fuel bowl. They also rock for the precise tunability, which is also its biggest problem-- they really need to be tuned RIGHT. I got 15mpg out of mine, in a big-block work truck, and it ran cleeeeeean.

I might be mistaken but arent' the Performers based on the AFB??

 

[Rot Box]

I might be mistaken but arent' the Performers based on the AFB??

AFB's (short for: A Fu....Oop's I can't say that on RME ) are the predecessor's of the Performers. AFB's and Performers from what I have seen all have Weber's "W" stamp on them as they had the original concept if I'm not mistaken.