Thread: Mechanical VS Electrical, Being Fuelish.

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Hiya,

OK, this may be a dumb question but,hey! I'm a dumb person.

I been toying with the idea of an electric fuel pump just to give that lobe on the cam a break.

But is it worth it?

It's on my 350 Chevy.

I'm hoping for more HP and better fuel economy.

But is it negligible?

Which is the best way to pass the gas?

Fuel pump isn't going to have anything to do with fuel mileage, it's only task is supplying fuel to the carb..... If you're not running low fuel pressure and just running on the street, not a lot of reason to switch to an electric pump.....

Thanks!

Wish I asked this question before I bought that regulator.

I have to agree with everything the others said about power and economy.

I run mechanical on my daily drivers and electric on my "toys". They tend to sit up longer than I would like and it's nice to be able to prime the carb before trying to start the engine.

The only other advantage of an electric is if the mechanical is in a hard location to get to(like some streetrods). The frame mounted electrics can be mounted where they are easier to replace.

Mike

The only good thing I would say for an electric pump on the street is a theft
deterant, mouting a toggle hidden somewhere out of sight

Yeah, I was thinking of a kill switch anyway on account of hearing cars just like mine are starting to disappear without the owners consent. But I can cut the distributor if it came to that.

What I was wondering is how much drag that mechanical pump is on the engine and would it be beneficial if the engine didn't hafta work to pump that pump.

It's true that my car is a daily driver but it's also my only toy right now. I'd like to do what it takes to get as much out of it as I can.

And on a budget too.

Originally Posted by Good Wrench

Yeah, I was thinking of a kill switch anyway on account of hearing cars just like mine are starting to disappear without the owners consent. But I can cut the distributor if it came to that.

What I was wondering is how much drag that mechanical pump is on the engine and would it be beneficial if the engine didn't hafta work to pump that pump.

It's true that my car is a daily driver but it's also my only toy right now. I'd like to do what it takes to get as much out of it as I can.

And on a budget too.

Maybe someone smarter than I am can explain it differently, but it has always been my opinion that it takes roughly the same amount of power to pump "X" volume of fuel from one place to another, whether it is in mechanical power or electrical power. If electrical, the alternator has to work harder to feed the electric pump and the crank has to turn the alternator, so.........where's the advantage, work-wise.

I guess it could be argued that one system is more efficient over the other, but I'm not convinced that there is that much difference. Certainly not enough to support the cost of a electric pump and regulator.

Seems like I remember an article in one of the car mags a few years ago where they dyno tested an engine with both types of pumps.

There was no measurable difference in power as I recall.

Well,

That save's me a few bucks anyway. Really I was only after horsepower but checking with my brainiac friend here confirms what Tech Inspector said. Same amount of energy either way.

Rats, I thought i'd get some cheap HP and have a nice shiney chrome plate where the pump usta be.

But i'm sure glad I don't hafta shell out $$ for something I don't need. Besides, I don't trust electric anyway.
Thanks!

Ohh PS, do I loose the regulator or leave it on?

Have to relate this story.

About 6 years ago I was drag racing pretty regular with my 65 GTO (389 tripower, 4 spd 3:90's) The car ran well and would put down 13.50's with ease.

One Sunday the car stalled doing the burn out. It started right up again and ran fine.

When I got home I started thinking about why it would stall. It had never done that before.

Well, when I think crazy things happen.....I decided the burnout was draining all the fuel out of the trips and the fuel pump couldn't keep up.

I put an electric pump in and guess what?

The next sunday at the same track under similar cobditions the car ran 13.20's WITH NO OTHER CHANGES!!!

True, an electric pump won't make more power, but if your fuel feed is marginal it will make your car quicker!!

Hmmm,

Yes I did forget to mention something else. I just married an Irish beauty fresh from Ireland who's never even seen a hotrod much less ride in one. Well, One night I was showing off to her and doing some high speed cornering and the car stalls. Starts up again but stalls anytime I change direction fast. I thought well, perhaps not enough fuel in the bowl?

I got a see through fuel inline filter and there is a bubble in the glass. However, There is a consensus that the stock pump should do fine even for the 4bbl. I can get a hi-volume mechanical pump but there's another $120.
I haven't really cornered fast with it since so I donnou.

Dang I didn't think of that.

It's a newish pump though but Yeah, i'll do the gauge thing. Good idea.