1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

do i need a better fuel pump?

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Old 03-14-07 | 12:08 AM
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rayadas's Avatar
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do i need a better fuel pump?

so i have an 83 with the 12a. i have a weber 45dcoe, full racing beat exhaust, brand new gas tank, carter fuel pump, mallory fuel pressure regulator, new fuel filter, the problem i have is that the fpr is open pretty much all the way, yet i still can't give it all the way. i also have problems when starting, it will start, run for a couple of seconds and then just die like it isn't getting any fuel. if you need more information to help me out let me know, otherwise thanks for the help
Old 03-14-07 | 12:24 AM
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Carter what? You should be good with the pump and fpr. More than likely, your fuel lines, pickup, intank screen are partially blocked.
Old 03-14-07 | 12:27 AM
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i have the CRT-P4594, like i said i have a new gas tank, so what would be the best way to clean the lines?
Old 03-14-07 | 12:48 AM
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Originally Posted by rayadas
so i have an 83 with the 12a. i have a weber 45dcoe, full racing beat exhaust, brand new gas tank, carter fuel pump, mallory fuel pressure regulator, new fuel filter, the problem i have is that the fpr is open pretty much all the way, yet i still can't give it all the way. i also have problems when starting, it will start, run for a couple of seconds and then just die like it isn't getting any fuel. if you need more information to help me out let me know, otherwise thanks for the help
Please define. "Yet I still can't give it all the way"?

When you are refeering to starting it and it runs for a few seconds and dies. Is this when the engine is first started and also when it sits for awhile and then is restarted?
Old 03-14-07 | 12:58 AM
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i cant give it full throttle, also when i get about 100mph it starts to chug. yes that is right with the starting problem, my thinking was that it just needed to be warmed up becuase i had it out the day b4 and once i was driving a while when i shut it off, it would start up pretty much no problem. the problem isn't consistant though. i'm not saying i really need to go faster, but i don't like having problems, any suggestions would be great--thanx
Old 03-14-07 | 11:37 AM
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The starting problem you are indicating is normal for that carb. Unless you have the choke cable fabricated so it would attach to the carb you will have to feather the throttle to keep it running until it warms up.

On the fuel issue you need to verify what pressure is going into the carb.
Old 03-14-07 | 11:44 AM
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I know i have that problem with holley but i just feather the throttle till it warms up and then it's good to go
Old 03-14-07 | 12:12 PM
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when the car runs good the fuel pressure is around 5 or 6. when it's not running good, the pressure is down to 2 or 3
Old 03-14-07 | 12:18 PM
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Sounds like either a restriction in the fuel line, a faulty pump, or loose wiring to the pump.
Old 03-14-07 | 12:22 PM
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Originally Posted by rayadas
when the car runs good the fuel pressure is around 5 or 6. when it's not running good, the pressure is down to 2 or 3
I don't understand?

The FPR should be set at 3.5-4PSI max, 5-6PSI it too much pressure for your setup. Remember this PSI after the regulator not at the regulator.
Old 03-14-07 | 01:16 PM
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The stock fuel filter is barely adequate for the stock fuel pump/carb setup. Since you need to run a bit more fuel with that carb, you might want to add another filter in parallel. That way, each filter only has to flow 1/2 of the volume.

Search for "dual fuel filter mod" and you'll find the instructions and photos on this mod...
Old 03-14-07 | 07:42 PM
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the psi is after the regulator. when i first got eveything, i had a holley fpr, when i turned that up too much the car would die. i haven't had that happen with this setup. i'll probably give the dual fuel filter mod a try to see if it would help my problem
Old 03-14-07 | 07:43 PM
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the psi is after the regulator. when i first got eveything, i had a holley fpr, when i turned that up too much the car would die. i haven't had that happen with this setup. i'll probably give the dual fuel filter mod a try to see if it would help my problem. also, i don't have a stock fuel filter, i have a fram g3 i think. could that also be causing trouble?
Old 03-15-07 | 07:07 PM
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so i did the dual fuel filter mod, it seems to have stopped the problem, i havn't been able to take it out on the road yet, but i am able to give it full throttle without killing it
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