HP Loss from Mechanical Fuel Pump

[72DMag]

Dropping a mostly stock 318 into a friends car just to go racing this summer. Went with a moroso electric water pump and not running an alternator to free up some HP. As I was working on the car I wondered how much HP, if any, would the mechanical fuel pump cause an engine to lose? Did a quick google search and had no luck finding any results.

Given a mostly stock 318 would there be any hp gain, even 1 hp?, by doing an electric fuel pump instead of the mechanical fuel pump?
Thanks!!

 

[Dan the man]

Dropping a mostly stock 318 into a friends car just to go racing this summer. Went with a moroso electric water pump and not running an alternator to free up some HP. As I was working on the car I wondered how much HP, if any, would the mechanical fuel pump cause an engine to lose? Did a quick google search and had no luck finding any results.

Given a mostly stock 318 would there be any hp gain, even 1 hp?, by doing an electric fuel pump instead of the mechanical fuel pump?
Thanks!!

With the use of a electric water pump and possibly going with a electric fuel pump and no alternator, you'll have to be sure that the battery is at full charge at all times other wise you will be robbing your ignition system of the voltage it needs to perform at capacity. I'd probably run a friction coated fuel pump eccentric instead of the electric pump. There's plenty of things that you can do to help power. Advance the ignition timing, curve kit, etc. Cold air kit, headers and a good flowing exhaust system.

 

[Dan the man]

Dropping a mostly stock 318 into a friends car just to go racing this summer. Went with a moroso electric water pump and not running an alternator to free up some HP. As I was working on the car I wondered how much HP, if any, would the mechanical fuel pump cause an engine to lose? Did a quick google search and had no luck finding any results.

Given a mostly stock 318 would there be any hp gain, even 1 hp?, by doing an electric fuel pump instead of the mechanical fuel pump?
Thanks!!

You said that it's mostly stock, is there a 4 barrel carburetor on it? What intake manifold you using.

 

[72DMag]

@Dan the man We have 2 optima red tops and the charging nodes on the back. Little genie and battery charger are in the trailer.

We did a comp cams swap and different springs on the 302 heads. Yes running a 4brl intake with a 650 demon carb. I have a couple intakes debating of doing air gap or a full dual plane like the LD340 (Really good intake).

I was unable to find any info or dyno runs or articles that compare same engine with and without mechanical pump so figured i ask.

 

[MOPAROFFICIAL]

5 hp tops. Average of 3hp.
Water pump is worth more.

 

[Dan the man]

@Dan the man We have 2 optima red tops and the charging nodes on the back. Little genie and battery charger are in the trailer.

We did a comp cams swap and different springs on the 302 heads. Yes running a 4brl intake with a 650 demon carb. I have a couple intakes debating of doing air gap or a full dual plane like the LD340 (Really good intake).

I was unable to find any info or dyno runs or articles that compare same engine with and without mechanical pump so figured i ask.

Sir, I think that you have a awesome combination. I was under the impression that the 318 was pretty much stock as a rock. What comp cam you running

 

[Dan the man]

5 hp tops. Average of 3hp.
Water pump is worth more.

Is that small power gain worth the money for a electric fuel pump? Would a friction coated eccentric be worth while?

 

[MOPAROFFICIAL]

Is that small power gain worth the money for a electric fuel pump? Would a friction coated eccentric be worth while?

I run a stock replacement 340 six pack fuel pump on my 410 small block.
I'm not worried about a fuel pump while making 560 hp.

 

[RustyRatRod]

MUCH less than 1HP. You can operate a mechanical fuel pump by hand. I mean really.

 

[72DMag]

We are running comp cams XE268H. Valves r stock size in the 302 swirl port heads.

I have a couple electric fuel pumps laying around so cost isn't the issue but If I get 5hp sounds like it would be worth it. Honestly shocked if it adds up to even 3hp but couldn't find any evidence to verify. Thanks for all inputs already fellas!!

 

[Dan the man]

I run a stock replacement 340 six pack fuel pump on my 410 small block.
I'm not worried about a fuel pump while making 560 hp.

Is that 560hp at the flywheel?

 

[MOPAROFFICIAL]

MUCH less than 1HP. You can operate a mechanical fuel pump by hand. I mean really.

X rpm...then its 5ish or whatever the exact # is

 

[Dan the man]

We are running comp cams XE268H. Valves r stock size in the 302 swirl port heads.

I have a couple electric fuel pumps laying around so cost isn't the issue but If I get 5hp sounds like it would be worth it. Honestly shocked if it adds up to even 3hp but couldn't find any evidence to verify. Thanks for all inputs already fellas!!

Nice cam

 

[RustyRatRod]

X rpm...then its 5

pppffffhhhhtttt

lol

 

[Dan the man]

pppffffhhhhtttt

lol

There's a lot of good information on the OP but I don't want to high Jack his post, so I'll just follow along and learn

 

[MOPAROFFICIAL]

Is that 560hp at the flywheel?

At the scrotum

 

[Dan the man]

At the scrotum

That's about 1.34 hppcid. Bet it's a runner.

 

[MOPAROFFICIAL]

That's about 1.34 hppcid. Bet it's a runner.

Made to DRAG race alright.
I bring a steel mesh satchel

 

[MOPAROFFICIAL]

MUCH less than 1HP. You can operate a mechanical fuel pump by hand. I mean really.

You've expertise in this field I take it?

 

[RustyRatRod]

You've expertise in this field I take it?

View attachment 1715885530

Not me evidently. What did you search to find that? lol

 

[72DMag]

LMAO

 

[James Clews]

I think you will find that the increased load through the alternator would be greater than the loss of running a mechanical pump and with that electric water pump that takes a lot of current to run this all has to be relpaced by the alternator!

 

[Jadaharabi]

MUCH less than 1HP. You can operate a mechanical fuel pump by hand. I mean really.

.
I want to see video of you pumping the pump at 6500 strokes per minute. Then tell me you only used 1 horsepower. Lol

 

[Oldmanmopar]

I left the alternator on and just shut it off in the water box so there is no drag. Then turn it on at the return lane. Keeps the battery charged if going back to back rounds

 

[Syleng1]

Love the switch idea…Either that or go with a very small alternator. Like one used on a small compact diesel tractor- 17- 20amps output. Belt driven and low drag. BUT helps keep voltage to 13.5-14.0.