Author Topic: Recommendations for fuel pump on a carbureted v8 conversion  (Read 4024 times)

Robert

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Re: Recommendations for fuel pump on a carbureted v8 conversion
« Reply #11 on: June 06, 2013, 02:43:33 AM »
I used a 4 cylinder Fiero fuel pump with a aftermarket regulator on my carbed sbc in my Diablo worked great. I can send you the fuel pump for free if you want it. I just pulled it out last month when I put in the LS4.
One more tip. A fuel injected 4 cylinder requires more psi, than a carb motor. Psi does NOT equal volume, you may experience a lean condition. I remember when I used a stock fuel pump on performance big block 427, the first time I raced someone, the carb ran out of fuel. I thought the engine blew up. I had forged pistons. A lean condition makes an engine run hot. You could possibly burn holes in you pistons. Good luck in your decision.
Robert, Journeyman experimental mechanic, Journeyman experimental painter.

tonypaul

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Re: Recommendations for fuel pump on a carbureted v8 conversion
« Reply #10 on: May 22, 2013, 10:37:16 PM »
I used a 4 cylinder Fiero fuel pump with a aftermarket regulator on my carbed sbc in my Diablo worked great. I can send you the fuel pump for free if you want it. I just pulled it out last month when I put in the LS4.

Robert

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Re: Recommendations for fuel pump on a carbureted v8 conversion
« Reply #9 on: May 22, 2013, 06:43:53 PM »
edelbrock 750 cfm
What is the cubic in displacement? The big mistake people usually make is too big of a carb. Here is carb size calc link http://www.csgnetwork.com/cfmcalc.html
I love edelbrock carbs, I had a 750 on a 427 chevy, it worked great! The graphing chart is a no brainer with the correct mettering rods and jets. Cubic inch displacement and rpm determind cfm needed. To big is not good! I used a carter street strip pump on my big block, 7 psi. Don't use a fuel pump made for a fuel injected motor. If you go external, remove the pump inside the tank, and make sure there is a strainer at the pick up point, on the bottom of the tank. ::thumbup
Robert, Journeyman experimental mechanic, Journeyman experimental painter.

jrule78

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Re: Recommendations for fuel pump on a carbureted v8 conversion
« Reply #8 on: May 22, 2013, 03:11:07 PM »
   That carb runs at 7psi fuel pressure.  You should have a regulator already if you were using the stock pump. However you decide to feed the carb I would recommend having a regulator and gauge.

CCIE

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Re: Recommendations for fuel pump on a carbureted v8 conversion
« Reply #7 on: May 22, 2013, 01:40:20 PM »
edelbrock 750 cfm

jrule78

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Re: Recommendations for fuel pump on a carbureted v8 conversion
« Reply #6 on: May 22, 2013, 12:24:26 PM »
   What carb are you using?

usmc_butler

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Re: Recommendations for fuel pump on a carbureted v8 conversion
« Reply #5 on: May 22, 2013, 11:17:19 AM »
If you put a in line fuel pump on, it will usually pull through a bad pump in the tank saving you the hassle and trouble of dropping the tank (i'm sure somebody will argue with me on this, I did this on a boat I had that the fuel pump was in the tank). Autozone sells different PSI pumps just ask them for a lower PSI (I will try to find the part number for the ones I use). I would trash the regulator and keep a PSI gauge cheap regulators are bad to stick or regulate the wrong amount, plus most all your carbs have a built in regulator. Just my .02 this is what I would do...



Dustin

CCIE

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Re: Recommendations for fuel pump on a carbureted v8 conversion
« Reply #4 on: May 22, 2013, 10:53:18 AM »
Thank You for the replies......

So is it a good idea to put a electric fuel pump in a carbureted v8 even with the substantial fuel pressure difference. My concern is with the regulator limiting the fuel to the engine would this not eventually burn the fuel pump (30 or so lb pressure coming from fuel pump down to 3-5 lb to the Corb)? In my F40 I have no pleasure and had a new electric fuel pump but after 2 years I see no fuel pressure (still there is a chance that the relay/wiring could be an issue) but I suspect I will need to drop the tank as fuel pump has hit the dirt (and that is a lot of work)

Thank You
CCIE

usmc_butler

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Re: Recommendations for fuel pump on a carbureted v8 conversion
« Reply #3 on: May 22, 2013, 08:21:05 AM »
CCIE

I use the ones Autozone sells, they work great, they are cheap and never had one go out on me. Just don't get the MR. Gasket ones..... This is like the one I usually get http://www.autozone.com/autozone/accessories/Airtex-Products-Electric-fuel-pump/_/N-25jpZ1z10pot?itemIdentifier=76843_0_0_

solrac

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Re: Recommendations for fuel pump on a carbureted v8 conversion
« Reply #2 on: May 21, 2013, 11:02:50 PM »
Ill be using a v8 but not carbureted. Fuel injection.
This is the fuel pump ill be using..

http://www.ebay.com/itm/160711897200?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

CCIE

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Recommendations for fuel pump on a carbureted v8 conversion
« Reply #1 on: May 21, 2013, 10:44:46 PM »
All.....

What's the recommendation for a carbureted v8 conversion in a Fiero, Currently on my F40 with a v8 there is the original electric fuel pump with a step down regulator but I am seeing no fuel pressure, I will be doing the usual tracing of the fuel pump wiring, relay fuse ect but wanted to know what have others done. I was told to put a mechanical fuel pump but that means lots of work including dropping the gas tank ect... Any advice is greatly appreciated...
 

CCIE