Well it finally happened.
My fuel pump went out. I have expected it for a while, its an original pump out of an 84 Fiero with 100000 + miles on it.

I will be replacing it with one from a V6 or I may price a corvette pump if someone knows the part number I need. I'm using a bypass regulator so it wont hurt to get the higher volume pump.
Its raining cats and dogs so I wont get anything done today but tomorrow I will drop the tank.

Advance auto parts has an Delco part for $50 and $79 I wonder what the differences are.

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What fuel system are you running? Carbureted, injected?

quote Originally posted by 1fatcat: What fuel system are you running? Carbureted, injected?

Carburetor, they had two available or I could order the Bosch. I ordered the Bosch and it will be in tomorrow morning, if not I will exchange it for the one they have on the shelf.
The higher PSI should also help with my top end, we will see when I get it in.
This will be my third Fuel pump I have changed in a Fiero so its not something I haven't done before. I may also take the time and wire in the oil pressure safety switch if they have one when I pick up the pump.

OK, but most carburetors run on 6-8 psi.

quote Originally posted by 1fatcat: OK, but most carburetors run on 6-8 psi.

I have a bypass regulator so thats no issue.

quote Originally posted by Jake_Dragon: I have a bypass regulator so thats no issue.

OH OH... what bypass reg??? Most pumps for carbs are less than 12>15PSI. If you throw in a pump producing 45+psi your reg will not 'regulate' down to 6psi.... and, if it does, you'll burn another. And, you'll be doing the work all over again....! Save yourself the grief and do it once, put in a carb pressured pump ie: less than 12psi.
Can you say float flooding...? think about it,...

My regulator has a return line so instead of dead heading against the regulator the extra pressure is sent back to the tank.
I have ran this setup with the stock pump for years now. It will hold 5 PSI steady.

quote Originally posted by Jake_Dragon: Well it finally happened. My fuel pump went out. I have expected it for a while, its an original pump out of an 84 Fiero with 100000 + miles on it. I will be replacing it with one from a V6 or I may price a corvette pump if someone knows the part number I need. I'm using a bypass regulator so it wont hurt to get the higher volume pump. Its raining cats and dogs so I wont get anything done today but tomorrow I will drop the tank. Advance auto parts has an Delco part for $50 and $79 I wonder what the differences are.

Typically, for a carburated car, I'd use a stock 4 cyl. Fiero fuel pump. A later model Vette pump or something like that puts out 40+ PSI of pressure. You only need 4 to 8 psi for a carbed engine. The 4 cyl. pump puts out 8 to 12 psi so it would need a regulator too.

The reason I don't like to use a high pressure/high volume pump on a carbed car is that the pressure coming from the tank & going into the regulator, is always going to be at 40+psi all the time & I see no reason to subject that side of the fuel system (& pump) to that kind of back pressure.

If you haven't had issues with the carb running out of gas on hard driving then there is no reason you'd need a higher volume pump.

Remembering that a carb has a fuel bowl in it & always has a bit of a reserve in it. It would take some extreme driving to run it out of gas on the street. High volume High pressure pumps are used on modern Port injected engines because the injection system doesn't have a reserve of fuel in it like a carbed engine has.....there is no float bowl to store a fuel reserve in. So for immediate throttle response, with no lag, a port injected engine needs the bigger pump.

I also would like to know which regulator you have & I'd suggest that you read the instructions for that regulator closely. Many times those instructions will say something about Max. incoming pressure limits.

Keep us posted on your progress.

Archie

[This message has been edited by Archie (edited 05-15-2011).]

Thank you for chiming in, I do have problems with the carb setup stumbling on hard turns. I hope by going to the higher pressure pump I will be able to keep up the pressure under extreme acceleration and hard corners I also hope it will keep up with any future modifications I may do.

I have an edelbrock carburetor and it doesn't have the same bowl size as the Holley I took off. That may be some of the issues. But its been a great carburetor

I don't recall what the regulator was but it was the top of the line when I got it a few years ago. I purchased it due to the fuel pressure fluctuation I had with the old single line dead head regulator. I don't see any numbers on the visible side I would have to pull it to read the numbers from the other side.
If I have time I will check it out.

If the pump doesn't work out I will put it on the shelf and install the lower pressure pump. Later down the road I hope to go to a fuel injected setup.

[This message has been edited by Jake_Dragon (edited 05-15-2011).]

quote Originally posted by Jake_Dragon: Thank you for chiming in, I do have problems with the carb setup stumbling on hard turns. I hope by going to the higher pressure pump I will be able to keep up the pressure under extreme acceleration and hard corners I also hope it will keep up with any future modifications I may do. I have an edelbrock carburetor and it doesn't have the same bowl size as the Holley I took off. That may be some of the issues. But its been a great carburetor I don't recall what the regulator was but it was the top of the line when I got it a few years ago. I purchased it due to the fuel pressure fluctuation I had with the old single line dead head regulator. I don't see any numbers on the visible side I would have to pull it to read the numbers from the other side. If I have time I will check it out. If the pump doesn't work out I will put it on the shelf and install the lower pressure pump. Later down the road I hope to go to a fuel injected setup.

Just a note to you on 'stumbling'.... Because the V8 is mounted traversely, most any carb will 'stumble with Hard cornering.It's because the gas(carb) sloshes around and allows the orifices to drain(or draw air), therefore stumble. There are some mods that can be done to retain the gas similar to oil pan oil retension, but I am not up to date with that. I have seen one guy actually cut his aluminum intake and reweld 90* to put his carb in the same linear dimensions as an inline engine, and yes, it did work. If I was to do it again... fuel injection, and never have a 'hiccup' 3/4 through a corner...PITA!
Even with a lower PSI pump and raising the pressure, I believe that 'hiccup' will remain. Let us know how it works out.
BTW I glad your using a return regulator, as a 'dead head' would almost certainly burn the pump out quickly or some other failure iminent.

[This message has been edited by cowans (edited 05-15-2011).]

[This message has been edited by 1fatcat (edited 05-15-2011).]

I finally just broke done and installed a bypass regulator - was using the dead head line in/line out style Holley regulator using a stock Duke pump. Had nothing but problems. Could not keep steady and constant pressure at the carb. At idle for any length of time, the pressure would rise until it pushed by the needle and seat - caused the motor to load up. Also had issues with dropping pressure at WOT causing a stumble - sometimes it would fall on it's face as if the fuel was shut off. While installing the new bypass regulator, I discovered the the vent line - originally went to the evap canister was plugged. The longer the car ran, the harder the pump had to work due to the vacuum being pulled on the sealed tank. I believe that it would get to the point where the pump could not overcome the vac and starve the motor for fuel. I put over 100 miles on the car yesterday with the new setup. No more loading up, constant steady 6 psi at the carb, no more stumbling and I went from getting 11mpg to just a tick over 18! Of course I did not flog on the car all day yesterday - just cruised it around town with about 50 miles on the Interstate cruizing @ 65 or less.

Not sure how the higher pressure V6 pump will work with the bypass as I have about 4 hours experience with one? I can't see where it would make any difference as the majority of the fuel/pressure is sent back to the tank but maybe, that much pressure up against the regulated side may cause fluctuation through the regulator and may cause pressure spikes that allows fuel to push by the needle and seat? Keep us posted on how it works Jake. It would be nice to have an alternative to the sorry Duke Fuel pumps out there these days. Sad to see your car on a flatbed!

Pat

P.S. Just to add, I changed out the Edelbrock carb for a QJet because I could not get a decent steady idle out of the Edelbrock. The QJet has a much cleaner consistent idle. Both carbs are new. I have played with a lot of Edelbrocks over the years and every one has had an issue with keeping a steady idle. I did loose a little bottom end performance with the QJet but OMG when those secobdaries open up! I have a rebuilt Holley w/vac secondaries I will try next. A buddy of mine just bought the Summit (Holley) and put it on his Nova - he likes it a lot. We may swap it on the Fiero for a little test and tune.

[This message has been edited by katatak (edited 05-15-2011).]

quote Originally posted by Jake_Dragon: Thank you for chiming in, I do have problems with the carb setup stumbling on hard turns. I hope by going to the higher pressure pump I will be able to keep up the pressure under extreme acceleration and hard corners I also hope it will keep up with any future modifications I may do.

No... pressure will not help.
Likely Is a design/maintenance issue(s) with carb you're using.

Once fuel is in bowl, any pressure doesn't matter. Fuel In bowl, fuel is at 0 pressure. Pressure Matter to needle valve that float must seal. Over pressure and needle won't seal.

Likely need a different carb...
Or better maintenance... Maybe Float is set wrong.

Any pump for 4 cyl EFI should easily handle V8 with carb. (w/o Nitrous wet system.)

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Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave (It's also at the top and bottom of every forum page...)

[This message has been edited by theogre (edited 05-15-2011).]

The tank is out and the pump is installed, I have to put the tank back in then I can set the fuel pressure and see where I am at.
The new pump was a little bit larger in diameter but it fit, I ended up with a Bosch pump for $80 if it doesn't work out I will order a Delco pump.

I know its been said but has anyone had any luck running an external pump? I know that they don't like to pull fuel but it wouldn't be that far as it would mount right by the inlet to the tank.
I have an external pump on my Vette and its done a pretty good job. Plus I can get a pump made for a carb setup.

Depending on your engine, it may already be set up to run a mechanical pump that bolts to the block? Not sure if there's room, and you would need a fuel pump push rod too. This is all assuming your engine is set up for it.

quote Originally posted by 1fatcat: Depending on your engine, it may already be set up to run a mechanical pump that bolts to the block? Not sure if there's room, and you would need a fuel pump push rod too. This is all assuming your engine is set up for it.

The axle would get in the way. Good idea but it wont work in a Fiero

Well I took the car for a shake down drive.
This street has a couple of sharp corners and I never cut out once.

[This message has been edited by Jake_Dragon (edited 05-16-2011).]