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Re: Can I run a Mechanical and Electric fuel pump together? [Re: Hemi Allstate] #1299134 09/07/12 11:06 PM 09/07/12 11:06 PM
Joined: Feb 2012 Posts: 394 Ohio M moparjoe360.4 enthusiast
moparjoe360.4 enthusiast M Joined: Feb 2012 Posts: 394 Ohio	My dad runs a parts store electric and a Carter high performance mechanical on his 6 pack with no issues but that's not a Holley blue, if u have that u don't need the mechanical pump.

Re: Can I run a Mechanical and Electric fuel pump together? [Re: domingo] #1299135 09/07/12 11:20 PM 09/07/12 11:20 PM
Joined: Nov 2006 Posts: 1,459 oklahoma F forphorty pro stock
forphorty pro stock F Joined: Nov 2006 Posts: 1,459 oklahoma	I ran a blue pump in series with a mech pump for years on a daily driver.The stock mech pump had no problem pulling fuel through the electric pump.Only had the electric on when racing or to fill the bowls of a dry carb.

Re: Can I run a Mechanical and Electric fuel pump together? [Re: forphorty] #1299136 09/07/12 11:52 PM 09/07/12 11:52 PM
Joined: Mar 2005 Posts: 862 Iowa State fan kilroy super stock
kilroy super stock Joined: Mar 2005 Posts: 862 Iowa State fan	If you used a dual pickup system 1 plumbed to the electric pump 2 and one with a one way valve on the pick up that goes to a Y then forward to the mechanical pump. That way the mechanical pump can suck through the one way valve line around the electric pump and when the electric pump is turned on it will pressurize the system forward to the mechanical pump but wont push fuel back to the fuel tank because of the one-way valve. But thats a lot of extra plumbing to do the same thing an electric pump will do by itself. Plus if the mechanical pumps diaphragm ever ruptures while the electric pump is on it will start to dump raw fuel directly into the crank case!!! 1973 Charger, former SE, former auto I'm not trying to be difficult, it comes naturally....

Re: Can I run a Mechanical and Electric fuel pump together? [Re: domingo] #1299137 09/07/12 11:54 PM 09/07/12 11:54 PM
Joined: Apr 2004 Posts: 12,339 somwhere S smokinwoody I Live Here
smokinwoody I Live Here S Joined: Apr 2004 Posts: 12,339 somwhere	I have to laugh at a few of these... for the last 15 years I have run both without a hitch and the only time I use the electric is when it was at the track... it sucks through the electric just fine...the rear pump is a Holley black pump rated at 140GPH at 14psi...the front mechanical pump is a modified Speedway (Carter ) that Barry Grant made...its stats are 140GPH at 14psi...so a regulator is used and I do have a small supercharger .....

Re: Can I run a Mechanical and Electric fuel pump together? [Re: smokinwoody] #1299138 09/08/12 12:13 AM 09/08/12 12:13 AM
Joined: Oct 2003 Posts: 3,698 NE Oklahoma V Von master
Von master V Joined: Oct 2003 Posts: 3,698 NE Oklahoma	Quote: I have to laugh at a few of these... No way it wont work...LOL... 72 RR, Pump gas 440, 452s, 3800 lbs, Corked, ET Radials,. 11.33@117.72. Same car, bone stock 346s, 9.5 comp, baby solid. 12.24@110.

Re: Can I run a Mechanical and Electric fuel pump together? [Re: Dan Halen] #1299139 09/08/12 12:15 AM 09/08/12 12:15 AM
Joined: Oct 2003 Posts: 3,698 NE Oklahoma V Von master
Von master V Joined: Oct 2003 Posts: 3,698 NE Oklahoma	Quote: therefore would also need a good fuel pressure guage..... ..... should already have one anyway. Um, why????? 72 RR, Pump gas 440, 452s, 3800 lbs, Corked, ET Radials,. 11.33@117.72. Same car, bone stock 346s, 9.5 comp, baby solid. 12.24@110.

Re: Can I run a Mechanical and Electric fuel pump together? [Re: Hemi Allstate] #1299140 09/08/12 05:13 AM 09/08/12 05:13 AM
Joined: Oct 2004 Posts: 16,479 Canada CrAzYMoPaRGuY I Live Here
CrAzYMoPaRGuY I Live Here Joined: Oct 2004 Posts: 16,479 Canada	Quote: Quote: Yes you can run an electric in series with your mechanical. You can turn on the electric when you need it, like when you are at the track. I did this many years ago on my 440 6 Pack Challenger. I plumbed a Blue pump with regulator. (you can add the Red pump without the regulator) If it is falling on its face on the top end it is starving for fuel. Thats what mine was doing and this solved the problem. I still run my Hemi Challenger with this set up. Kind of an old school approach, but it works. I did it using a Carter electric pump. I only turned it on to prime the system if the car had been sitting, and then whenever I wanted full power for a run, be it street or strip. EXACTLY what I did with my Demon, and EXACTLY what I am doing with my 1967 Charger!! CrAzYMoPaRGuY

Re: Can I run a Mechanical and Electric fuel pump together? [Re: CrAzYMoPaRGuY] #1299141 09/08/12 06:43 AM 09/08/12 06:43 AM
Joined: Dec 2009 Posts: 20,647 in a cattle trailer down by th... G Guitar Jones Paddle faster! I hear banjo music!
Guitar Jones Paddle faster! I hear banjo music! G Joined: Dec 2009 Posts: 20,647 in a cattle trailer down by th...	I can't imagine the mechanical being able to suck through that Holley pump, but if you guys say you've done it who am I to say you can't? "Follow me the wise man said, but he walked behind" '92 D250 Club Cab CTD, 47RH conversion, pump tweaks, injectors, rear disc and hydroboost conversion. '74 W200 Crew Cab 360, NV4500, D44, D60 and NP205 divorced transfer case. Rear disc and hydroboost conversion. 2019 1500 Long Horn Crew Cab 4WD, 5.7 Hemi.

Re: Can I run a Mechanical and Electric fuel pump together? [Re: Guitar Jones] #1299142 09/08/12 08:26 AM 09/08/12 08:26 AM
Joined: Apr 2004 Posts: 12,339 somwhere S smokinwoody I Live Here
smokinwoody I Live Here S Joined: Apr 2004 Posts: 12,339 somwhere	Quote: I can't imagine the mechanical being able to suck through that Holley pump, but if you guys say you've done it who am I to say you can't? if any of you ever disconnected the fuel line at the carb or in this case at the mechanical pump, you will find a very steady flowing stream of fuel..I mean flowing as if a pump was on!!!...and this is thru any electric pump in the rear... so there is no effort on a mechanical fuel pump's part in sucking thru the electric pump...

Re: Can I run a Mechanical and Electric fuel pump together? [Re: smokinwoody] #1299143 09/08/12 09:01 AM 09/08/12 09:01 AM
Joined: Oct 2003 Posts: 21,345 Marysville, O-H-I-O 70Cuda383 Too Many Posts
70Cuda383 Too Many Posts Joined: Oct 2003 Posts: 21,345 Marysville, O-H-I-O	I don't understand why the desire to have 2 pumps. if you're going to put on an electric pump thats capable of delivering enough fuel on it's own, then why keep the mechanical pump? why not just bypass it, remove a few pounds of weight, and keep the fuel cooler. what benefit do you GAIN by keeping the mechanical pump after adding an electric? Photobucket sucks

Re: Can I run a Mechanical and Electric fuel pump together? [Re: domingo] #1299144 09/08/12 10:04 AM 09/08/12 10:04 AM
Joined: Jan 2003 Posts: 24,562 Brookeville, Md Mr.Yuck Not enough dumb comments...yet
Mr.Yuck Not enough dumb comments...yet Joined: Jan 2003 Posts: 24,562 Brookeville, Md	I did it for a few years. I had a mild 440 w/ a Paxton. I used the eletric pump at the track or when I was going to get on it. I used the carter street/strip mech pump and their electric as well. If I had it to do over agin I'd just use a realy good mech or a straight up eletirc. Forget to turn on the electric and at about the 1000 foot mark your pistons start to burn up...AMHIK. Not sure about you combo but I ran a 11:1, 548 soild cam 440-6 w/ a Stock (autozone) Hemi pump and 3/8 w/o issue. Maybe you need to raise your float levels, you could also have an electrical problem. I'd start w/ the basics before you add or spend money. [IMG]http://i66.tinypic.com/pui5j.jpg[/IMG] Coming soon!!!!

Re: Can I run a Mechanical and Electric fuel pump together? [Re: Mr.Yuck] #1299145 09/08/12 12:05 PM 09/08/12 12:05 PM
Joined: Jan 2003 Posts: 9,670 Lima, Peru domingo OP EL Master
domingo OP EL Master Joined: Jan 2003 Posts: 9,670 Lima, Peru	I just plumbed the electric blue pump and ditched the mechanical with a bloick off plate and added a regulator.-....like its supposed to be done. Thanks for all the replies....now I know that it is doable to have a mechanical in betweenm the electric fuel pump and carbs.....but yes, why do it that way? Only thing would be the annoying sound of the electric pump on a car thats driven on the street...but oh well---- BTW the car runs great....Ill test it at the track tomorrow and Ill see if the problem's been solved! Thanks!!!

Re: Can I run a Mechanical and Electric fuel pump together? [Re: Hemi Allstate] #1299146 09/08/12 01:34 PM 09/08/12 01:34 PM
Joined: Jan 2003 Posts: 2,431 USA S SSAAHemiFan top fuel
SSAAHemiFan top fuel S Joined: Jan 2003 Posts: 2,431 USA	holley red pump with mechanical pump here - red pump was only used in hot weather, racing, or to prime system I installed a tee at the inlet and outlet of the electric pump with a bypass loop to help the pump run cooler and it allows fuel to pass thru easier then when the electric pump is off. Car ran 10:50's, 3/8 line with no starvation issues - pump is 12 years old Seems funky - but it works

Re: Can I run a Mechanical and Electric fuel pump together? [Re: SSAAHemiFan] #1299147 09/08/12 02:06 PM 09/08/12 02:06 PM
Joined: Jul 2006 Posts: 4,319 Puyallup, WA S StealthWedge67 master
StealthWedge67 master S Joined: Jul 2006 Posts: 4,319 Puyallup, WA	Carter 4862 mechanical pump being fed by stock 5/16" line into an 830cfm DP on a 451 here. Car weighs 3750 and runs 11.90's @ 113 mph with no fuel issues. I've had electric pumps before.... didn't like the noise and the hassle. LemonWedge - Street heavy / Strip ready - 11.07 @ 120

Re: Can I run a Mechanical and Electric fuel pump together? [Re: 70Cuda383] #1299148 09/08/12 02:28 PM 09/08/12 02:28 PM
Joined: Nov 2006 Posts: 1,459 oklahoma F forphorty pro stock
forphorty pro stock F Joined: Nov 2006 Posts: 1,459 oklahoma	Quote: I don't understand why the desire to have 2 pumps. if you're going to put on an electric pump thats capable of delivering enough fuel on it's own, then why keep the mechanical pump? why not just bypass it, remove a few pounds of weight, and keep the fuel cooler. what benefit do you GAIN by keeping the mechanical pump after adding an electric? When i bought my first Holley blue back in the 80s, i heard that they weren't very reliable in a continuous duty(daily driver) application. So i kept the mech and turned the electric on when racing,etc. That first Holley blue lasted for years. When i switched from the factory 5/16 fuel line to 1/2 inch, i took off the mech. The Holley blue failed after about a year. Replaced it with a new one, it lasted a couple of years, bought another, it lasted a couple years. Switched to a red and it's been going for a long time . So... my long winded point is... Factory mechanical pumps are cheap, electric pumps are not. The life of an electric pump is greatly extended if it is rarely on. A mechanical pump has never left me stranded on the road, an electric has .Sure,a big ,fat high output mech would be fine for all my stuff but i like the electric for other reasons too.Like priming the system after the car has been sitting without having to crank the engine forever . Also as a way of checking for leaks after doing any fuel system work without having to start the engine.

Re: Can I run a Mechanical and Electric fuel pump together? [Re: forphorty] #1299149 09/08/12 06:11 PM 09/08/12 06:11 PM
Joined: Dec 2003 Posts: 531 USA 5 540DUSTER mopar
540DUSTER mopar 5 Joined: Dec 2003 Posts: 531 USA	who the heck wants to listen to a loud ace holley pump in a street car if you don't have to.That is one noise I can't stand.But at the track you uncork them headers and turn that holley pump on and all you will hear is sweet music.

Re: Can I run a Mechanical and Electric fuel pump together? [Re: Guitar Jones] #1299150 09/08/12 08:33 PM 09/08/12 08:33 PM
Joined: Apr 2005 Posts: 1,505 TN S SCATPACK 1 pro stock
SCATPACK 1 pro stock S Joined: Apr 2005 Posts: 1,505 TN	Quote: You can run an electric pump with the mechanical but you won't be able to turn it off and expect the car to still run. I have this mechanical and electric set up on my 440 and do not use the electric pump except at the track. I have never had an issue this way. Before adding the high pressure mechanical, I wore out 2 Holley electric pumps trying to run them on the street. They just do not seem to hold up well for me with long drives/crusies. After I added the mechanical pump, I have not had any problems. I have not tried to run it at the track with just the mechanical pump. But i have used it a lot on the street with the electric pump off and no issues at all. Good luck Old Geezer Racing

Re: Can I run a Mechanical and Electric fuel pump together? [Re: SCATPACK 1] #1299151 09/09/12 12:17 AM 09/09/12 12:17 AM
Joined: Mar 2005 Posts: 862 Iowa State fan kilroy super stock
kilroy super stock Joined: Mar 2005 Posts: 862 Iowa State fan	Last comments from me. Then you can do as you please. Regarding fuel coming through a Holley style vane pump. Yes fuel will go through them but it is very restricted, believe me I just had to change a electric pump when I broke its casing by installing a pipe thread to deep. (lesson learned there) The flow through the line when it is not attached to the pump is has A WHOLE LOT MORE FREE FLOW through it. When the line is attached to the pump it will run out but not much, as I could do my work with out worry about emptying the tank (or drowning). In regards to worrying about the longevity of electric v mechanical. I think it is a wash as mechanical pumps get weak and fail too. The only thing I can say for the noise is lots of rubber parts between the metal pieces of the pump/mounting areas. 1973 Charger, former SE, former auto I'm not trying to be difficult, it comes naturally....

Re: Can I run a Mechanical and Electric fuel pump together? [Re: 70Cuda383] #1299152 09/09/12 11:50 AM 09/09/12 11:50 AM
Joined: Oct 2004 Posts: 16,479 Canada CrAzYMoPaRGuY I Live Here
CrAzYMoPaRGuY I Live Here Joined: Oct 2004 Posts: 16,479 Canada	Quote: I don't understand why the desire to have 2 pumps. if you're going to put on an electric pump thats capable of delivering enough fuel on it's own, then why keep the mechanical pump? why not just bypass it, remove a few pounds of weight, and keep the fuel cooler. what benefit do you GAIN by keeping the mechanical pump after adding an electric? In MY Charger's case the reason was.... NOISE!!!!! I couldn't stand the sound of a noisy electric pump while cruising through town. CrAzYMoPaRGuY

Re: Can I run a Mechanical and Electric fuel pump together? [Re: domingo] #1299153 09/09/12 12:23 PM 09/09/12 12:23 PM
Joined: Nov 2009 Posts: 2,275 Desert Tracker H HYPER8oSoNic top fuel
HYPER8oSoNic top fuel H Joined: Nov 2009 Posts: 2,275 Desert Tracker	Quote: Hi! Last time I hit the track with my stock 71 440-6 car I think I had some fuel starvation issues.... When I was in 3rd gear and peak RPMs I had the motor die intermitently, kinda like if the cylinders were getting no spark....thing is, when the car is driven normally that never happens, so what Im guessing is that on a pass at wide open throttle Im sucking dry the 6 pack fuel bowls....am I thinking right??? Well, now to fix this I was wondering if I could run a Holley Blue pump (I already have it) out of the gas tank and then pump it through the stock mechanical pump. I would like to avoid removing the stock mechanical if possible. I would only turn the electric pump for ging down the 1/4 mile. Can I do it like that? Thanks! D To answer the questions - YES!! This "old school" fuel system upgrade is timeless for carbuerated motors. Just wire the electric fuel pump with it's own on/off switch. Put the pump inline with the suction line from the tank and output side heading towards the input side of the mechanical pump. As a method of less flow restriction, try to upgrade to 3/8" steel fuel line, if you can. When you buy the electric pump, try to buy a "similar" (read: slightly higher)flow output pump than the mechanical. Example: 12psi output electric pump feeding into a 8psi mechanical pump. Got it? Remember, 6-packs NEED a lot of fuel, just like HEMIS or Max-Wedges!! "Stupidity is Ignorance on Steroids" "Yeah, it's hopped to over 160" (quote by Kowalski in the movie Vanishing Point 1970 - Cupid Productions)

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