Opel GT Forum banner
1 - 5 of 5 Posts

· Registered
47 Posts
Discussion Starter · #1 ·
I got a question. my 69 gt is not getting enough fuel from the mechanical
pump. I would like to put in an electric fuel pump. the question is what
pressure pump should I install? this is what I would like to use, just don't
know which one, these are from jcwhintey.com

a.. Replace or bypass malfunctioning original
b.. Prevent hot-weather vapor lock; ensure easier
cold-weather starts
c.. Work with all fuels and additives
Our smallest pump-3"H x 2-1/2"W x 3"L, weighs just 18
oz. Mount easily in tight spots-no need to remove old pump in most
instances. Not for vehicles with fuel or throttle body injection, nor marine
engines. Can also be used as utility pump for industrial and farm machines.
Includes hardware and instructions. Choose the pressure/delivery capacity
best suited to your needs.

Click product SKU for more detailed information
Item Description Unit SKU# Price Qty. Order
12-volt Electric Fuel Pump, 1-1/2 to 3-1/2 psi, 25 GPH
Deliver Capacity Kit ZX738895X $41.99
12-volt Electric Fuel Pump, 2-1/2 to 4-1/2 psi, 30 GPH
Delivery Capacity Kit ZX738896N $41.99
12-volt Electric Fuel Pump, 4-1/2 to 6 psi, 35 GPH
Delivery Capacity Kit ZX738897T $41.99
12-volt Electric Fuel Pump, 7 to 9 psi, 45 GPH Delivery


· Über Genius
10,251 Posts
I would worry about the GPH more than pressure. It takes almost no pressure to have a float bowl fill up. The 30gph should be fine. It will give you a max of 4.5 psi which is easy enough for the float needle to shut off. If the float overfills with this pump, then check the needle valve. The max GPH your opel should use under extreme driving is 4 so you won't have to worry there.

As far as whether or not you should bypass the mechanical?
Two things to consider...
First, after market pumps will often die suddenly leaving you stranded. If you have your mechanical in the car as well, then there is less strain on the electric.
BUT, It is entirely possible for the mechanical pump to <i>restrict</i> the fuel flow which would cause the electric to fail early and still not give the desired fuel availability you need.

If it were me and I were going to an electric... I would bypass the manual and leave the electric easy enough access in case of a failure. (this actually happened to my first opel).

· Registered
47 Posts
Discussion Starter · #3 ·
i have both in my fiat and only use the electric pump, the other leaks bad. i never had a problem and the car starts right up, even in the cold.

i can hear the gas going into the carb, but car wont stay running unless i spray gas in.

· Old Opeler
5,564 Posts
wcarter4 said:
i can hear the gas going into the carb, but car wont stay running unless i spray gas in.
Check the level of the fuel in the carb fuel bowl IE; the float level it may be low or the idle passages my be clogged with rubbish.

· Über Moderator
6,674 Posts
And DON'T let the pump pressure exceed 3 1/2 psi. Webers (and Solex's, if you are still at that stage) tend to flood at higher pressures. So either use a pump rated to not exceed 3 1/2 psi, or install a pressure regulator. JM2CW
1 - 5 of 5 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.