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80cap
What is the best fuel pump option for a carbed car? Also
has any one used an inertia safety switch for an emergency
shut off?
Thanks Brian
jmill
Been asked a lot. Do a search or click link below.

http://www.914world.com/bbs2/index.php?showtopic=273707

How about adding an oil pressure switch? Did it on several cars. No oil pressure means the pump shuts off. Pressure switch supplies ground for relay that switches pump. You'd need to have a way to bypass switch if car sat for a while and you needed to prime carbs. You can do that multiple ways.
80cap
Thanks!
I had a kit car in the late 90's and it used a mustang two system which had the
safety switch mounted in the trunk. If you had a small bump it would open the circuit
and kill the pump. To reset you just pushed in the breaker button. I think I'll
try to incorporate one of these.
Brian
McMark
Just bought one of these controllers, but haven't installed it yet. Looks like a GREAT setup for carbs.

http://www.revolutionelectronics.com/Fuel_Pump.html

QUOTE
Fuel Pump Controller
This universal electric fuel pump controller is designed for cars and trucks being upgraded from a mechanical fuel pump to an electric inline or in-tank fuel pump.

Pump only runs if there is a tach signal from the ignition.
Primes the pump for three seconds at initial key-on.
Includes a 7.5 amp circuit breaker.
Includes an internal relay.
Includes 15 feet of 16 gauge wire to energize the fuel pump.
One year warranty
30 day Money Back guarantee
$62.99 PN 12003


IPB Image
80cap
Thank Mark
I'm having a senior moment, it was a fox body mustang which had the inertia switch.
When you get the controller installed please let us know how it works.
Brian
jmill
That's a cleaner setup than the pressure switch. No need for manual prime switch or an extra relay. Just toggle key a few times and your done.
toolguy
An low oil pressure switch / ignition cutoff on a carb'ed engine is almost useless. .
First off, the float bowls have enough gas to keep running 1-2 minutes after you have lost all oil pressure
2nd, when starting, no oil pressure but you need the fuel pump to run before cranking to refill the fuel bowls .
McMark
QUOTE(toolguy @ Jan 13 2016, 09:24 AM) *

An low oil pressure switch / ignition cutoff on a carb'ed engine is almost useless. .
First off, the float bowls have enough gas to keep running 1-2 minutes after you have lost all oil pressure
2nd, when starting, no oil pressure but you need the fuel pump to run before cranking to refill the fuel bowls .

1. Unless you're in an accident where the fuel pump keeps pumping fuel onto the ground/motor/etc. That's VERY USEFUL. tongue.gif

2. As you mentioned there is always fuel in the bowls, unless you leave it parked for months.
jmill
QUOTE(toolguy @ Jan 13 2016, 10:24 AM) *

An low oil pressure switch / ignition cutoff on a carb'ed engine is almost useless. .
First off, the float bowls have enough gas to keep running 1-2 minutes after you have lost all oil pressure
2nd, when starting, no oil pressure but you need the fuel pump to run before cranking to refill the fuel bowls .



The idea is not to save the engine, it's to save you. You don't want the fuel pump to continue running when you get knocked unconscious in a bad wreck. If a fuel line gets severed or the car flips over you'll have gas flowing out of the carbs or the lines until the key gets switched off.

Like you said, there's fuel still in the float bowls. If the car hasn't been sitting for long periods it starts up just fine. Worked great on my bug. 5 psi pressure switch is located just under the 009 distributer.
jmill
Damn, we both replied at the same time. I still think your gizmo is a cleaner solution with the 3 second prime option.
CatDaddy60
Actually in the left side of the trunk wall on a 90s to 2000 era mustangs is a small inertia switch that is very easily wired to a fuel pump circuit I bought one from a junkyard for 2 bucks,
SKL1
Put the inertia switches from Summit Racing in both cars. Mounted in front trunk so I can access the button easily if need be.

That electric arrangement above looks slick- if I'd known about it before, may have gone that route.
Bulldog9
QUOTE(80cap @ Jan 12 2016, 06:43 PM) *

What is the best fuel pump option for a carbed car? Also
has any one used an inertia safety switch for an emergency
shut off?
Thanks Brian


I am running the carter low pressure rotary pump from CB Performance, low pressure high volume. For cut off, I used a low pressure (4lbs) normally open oil pressure switch for a safety on the fuel pump. I left all the stock wiring in place, and jumped the dual relay terminals (on a 912E) with the switch. This allowed me to retain the stock 'on' condition when starting and pump will shut off if engine stalls, etc when oil drops below 4lbs. When hot, takes 10-15 seconds or so to shut off. Not ideal/immediate but works well. This is the wiring diagram I used, not sure if this is the same relay for the 914, it has the same motor as the 914, but different FI system
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