Mechanical or electric fuel delivery?

[Toronado]

Does a carb. perform better with OEM mechanical fuel pump,
or a electric fuel pump? I heard that an electric fuel pump
delivers a more constant fuel flow, compared to the mechanical pump.
It seems like a simple conversion, I just dont want to run out of fuel
at WOT, I was told that the stock pump on my 455 is not sufficient,
but i really dont know if its just another racers myth/ like bigger is all ways better.

[omaha]

I'm sure you can make the mechanical pump work just fine. Usually it's not the pump, it's the size of the original fuel line and the restriction from all the bends in the lines. Also, HP mechanical pumps are available. There are some advantages to electric pumps. Yes put out a constant pressure but is a constant pressure always needed [like at idle for instance].  Carbs like volume and just enough pressure to keep up with the demand. And, actually, the mechanical pumps do better on the "suction side of the equation" than alot of the electric pumps. [some of which need gravity to help them]. The only problem nowdays is the newer fuels and the availability of quality mechanical pumps. One thing that an electric pump does better is to fill the fuel bowl before the car is started. So in the winter if you do not have a choke and it is cold outside you can give it a couple squirts and you know the bowl wil not be dry. This makes cold starting somewhat easier. Of course their are inherent dangers to an electric pump. Like not shutting off in an accident and burning you up.  Then there is the extra demand of the electrical system and having to run all the wires and of course the mounting (etc,etc). If you just have one Q-jet on a fairly hot motor, I think you shoud be able to get by with a mechanical pump and the appropriate fuel lines. If you need more fuel, Carter still makes high volume mechanical pumps [others too]. (long answer I know)

[Toronado]

Good information, and interesting to know that the mechanical fuel pump
is not giving to much pressure at idle. Some have told me that there is wear involved
with the mechanical pump on the cam shaft, along with the resistance of the rod needing
to be pushed. I have seen lighter and stronger rods for the mechanical pumps, I guess theres positive
and negatives with both. thanks again.

[Schurkey]

Some have told me that there is wear involved with the mechanical pump on the cam shaft,

Not on an Oldsmobile.  Fuel pump eccentric is bolted onto the front of the camshaft.

along with the resistance of the rod needing to be pushed. I have seen lighter and stronger rods for the mechanical pumps

We ARE talking about an Oldsmobile...right?

There's no Chevy-style fuel pump pushrod on an Olds.






The nice thing about electric fuel pumps is that they PUSH the fuel forward; and if you choose the right pump, it pushes at considerably higher pressure than the carb would otherwise be able to handle.   That way, the smallish stock fuel plumbing can still be used for fairly high horsepower applications.  In addition, the pressurized fuel won't vapor lock.   You regulate that pressure downward somewhere in the engine compartment.

One downside of electric pumps is that many of the most popular ones are noisy.

[Toronado]

Not on an Oldsmobile.  Fuel pump eccentric is bolted onto the front of the camshaft.
We ARE talking about an Oldsmobile...right?

There's no Chevy-style fuel pump pushrod on an Olds.






The nice thing about electric fuel pumps is that they PUSH the fuel forward; and if you choose the right pump, it pushes at considerably higher pressure than the carb would otherwise be able to handle.   That way, the smallish stock fuel plumbing can still be used for fairly high horsepower applications.  In addition, the pressurized fuel won't vapor lock.   You regulate that pressure downward somewhere in the engine compartment.

One downside of electric pumps is that many of the most popular ones are noisy.

Ya i owned chevy's all my short life, this is my first oldsmobile, even more od ball
a toronado. I ran electric pumps on my el camino, corvette, caprice, with good results
and your right rat-a-tat very loud but no lack of pressure, and removed that heavy rod.
I just wanted related info on the carbs preferance, which sounds like which ever pump
can feed the engine, dont want my 375 horses running outa feed at high RPM's.
HAHA