DO YOU USE A RETURN FUEL LINE

[ACUDANUT]

 I Never have.  

[Ghoste]

I do, but my car came with it.

[Charger-Bodie]

my 68 doesnt have it but my 69 does.

[tan top]

yes , from the carb to tank 

[1974dodgecharger]

Not needed really....though heated fuel without a return is not a myth.  Watch road kill where they drive both the camaro and super bee fried burger talks about not having a fuel return line just boils their gas away.....it was also hot out.....if u live in cold weather not needed.......

[fizz]

I understand it helps for vapor lock, which sucks. So why wouldn't you run one?

[1974dodgecharger]

I understand it helps for vapor lock, which sucks. So why wouldn't you run one?

hellcat engine don't have one, lol...maybe if you run a high powered engine car you don't need one?

I have one.....just put one in I say...why not right.

[Lord Warlock]

My 69 had one when I got it, but I was getting vapor lock with the original line, I removed it from the front of the engine and capped off the line itself, and it remained that way until I replaced the fuel line last year and didn't get a return line since I wasn't using it anyway.  Now I'm not sure if its needed or not.  My car hasn't been driven since the new line went in. 

[ACUDANUT]

yes , from the carb to tank 

Pic's ?

[tan top]

yes , from the carb to tank 

Pic's ?

, ok ! watch this space 

[ACUDANUT]

10-4 

[A383Wing]

My Chargers & Pontiac don't, my Shadow does, my Dakota does not, my PT does not

[green69rt]

Vapor lock (I thought) is when gas in the line vaporizes and then fills the mechanical pumps cavity or the carburetor fuel bowls, either way it starves the engine of fuel.  Old cars with the mechanical pump at the engine have to suck the gas thru the long gas line which creates a vacuum on the gas in the line, also the line is usually exposed in the engine compartment, a good recipe for causing the gas to flash to vapor.   Adding the vapor seperator allows any vapor created to vent back to the gas tank.  New cars don't have them because almost all cars now use an electric pump back by the tank or in the tank.  This keeps the whole line pressurized and also pumps the gas close to the cool gas tank.

There have been several discussions about the pro's and con's of the separator on this forum.  Try this one.

http://www.dodgecharger.com/forum/index.php/topic,117277.msg1454963.html#msg1454963

[tan top]

10-4  

 

have a 3/8 " supply  & a 5/16" return  ,  was / did originally wanted to use 1/4" return from carb , but could not find the   correct female inverted flare fitting for the  thunder AVS  ,  so went with  5/16" as a return ( had a reel  that size hard line already   )
I used a restrictor in the carb fitting , forget what size think .060   , anyways it was the same size metered return restrictor as a stock vapor separator .

pictures below was my first  test bend up in hard line  both feed & return for a return line set up  ,  ( don't  take any notice of the  bends    it was ,   nothing fancy , & jerry rigged with cable ties etc   )  only went with simple stuff   ,   did not see the point getting carried away , if it did not work  properly . but it !  works really well  

have got stainless hard line now in both sizes  , so going to bend up proper shaped  stainless lines  , less rubber hose etc  ( although been saying that for the last 3ish years   )will do it one day   ,   &  fabricate a few support brackets ( not need though the lines are rigid  & to not move or vibrate with the motor running etc.



also  just recently  ,   put my electric fuel pump back on  , switch operated , few seconds burst , before cranking  when  been left a few days weeks

[ACUDANUT]

How would that work on a Holley ?

[tan top]

 

think some holley float bowels come threaded both sides for fuel line fittings ,  i'm no expert though ,  or would have to cut / tap a   thread  , & have two return lines one for each bowel  ,

have a look at the link below  E booger done  a holley .

http://board.moparts.org/ubbthreads/ubbthreads.php/ubb/showflat/Number/6209669/site_id/1


how I came to do mine was  ,  I switched back to a mechanical pump  after the resto ,    would run  good  , strong idle  ,  go out for a blast on a hot day  , really give it a hammering  , get stuck in traffic or let it idle  for  5 ten minutes or more  , temperature gauge would  climb to 190 -195  , & the idle would get erratic almost stalling , black smoke out the tail pipe , , blip the throttle  , would be ok for a minute then start wanting to stall again , coupled with a puff off black smoke out the tail again  , sometimes at the point of stalling , if blip throttle , nothing would happen , gas boiled away in carb ,  verified this with a fuel pressure gauge & a temporary clear plastic fuel filter , only had these problems after swapping to a edelbrock carb & a aluminium in take .
, would be a pain hot starting  too ,  I wernt  running a vapour separator  , so I put one of them fuel filters with a return nipple on the  top side  ,  did not make any difference  ,  
open the hood   10 minutes after shutting it down  , with heat soak ,  engine bay reeks of the  smell of gas , fuel boiling , on a hot day  ,  I don't think  the  stock unsilenced air cleaner helps  , heat rises up through the gap underside  ,  anyways  , worked out  how I was going to run this return line  ,  & its been perfect ever since  , would have liked to run a 1/4" , imo would have been neater .

[ACUDANUT]

I looked at that site. I do not see a incoming fuel line. Also, on that Holley, the fuel lines looks horrible. Just my opinion 

[tan top]

yes it don't show much  of  the feed line  ,

if I were running a holley carb , think this is how I would run the lines   , if I had just a electric fuel pump ,  run it up & along the fire wall  , see below  ,  thinking this route because the duel feed  inlet line  runs into the distributor or close to  

white fuel feed , green return . in hard line

  B if mechanical pump would run the lines  , as close to stock as possible ,  

[ACUDANUT]

You can't run fuel lines on Drivers side of carb.  No fuel entry on that side of carb. 
Reason I am asking is I run Electric fuel pumps and the pressure seems too high.

[Charger-Bodie]

Some Holley bowls have both sides threaded. One side is often plugged. Most are not threaded and yours obviously is not. You may just need to get a regulater.

[cdr]

http://image.hotrod.com/f/76110798+w660+h495+cr1/mount-aeromotive-regulator-on-fuel-log-at-carburetor.jpg


this is how a holley is done,, supply on the right, return on left, you have to use a regulator that is for fuel return.

[ACUDANUT]

Some Holley bowls have both sides threaded. One side is often plugged. Most are not threaded and yours obviously is not. You may just need to get a regulater.

I would say......Very few

[tan top]

You can't run fuel lines on Drivers side of carb.  No fuel entry on that side of carb.  
Reason I am asking is I run Electric fuel pumps and the pressure seems too high.

Some Holley bowls have both sides threaded. One side is often plugged. Most are not threaded and yours obviously is not. You may just need to get a regulater.

  what C B  said        ,  fitting a regulator would be the quickest fix ,  you can get them with a return line  ,  that would be the one I would go for , don't think deadheading a electric fuel pump is a good idea  

i'm not up on holley carbs , no idea on  the max psi for the needle seat   ,  what pump you got ?  holley red tops are a good pump ,  the marine version has a  built in connection for a return line  ,  seem a good idea ,   don't see whats stopping you using a marine version of the pump on a street car  , unless i'm missing something  


http://www.jegs.com/p/Holley/Holley-Electric-Fuel-Pumps/745123/10002/-1

edelbrocks are  really sensitive to psi  6psi max   , have a 6.5 psi  pump , never had a prob though with or with out return  line  .

[ACUDANUT]

I'm using a Holley Red Pump.  I wonder what kind of shape the inside of the original return line is in.  Got any idea on prices for a new one. ? Thanks 

[Jaysick]

Some Holley bowls have both sides threaded. One side is often plugged. Most are not threaded and yours obviously is not. You may just need to get a regulator.

I would say......Very few

Im about to put an electric pump in, never ran with one before so ive been reading up on it.  Most everything I've read or been told pretty much state you must run a regulator when using an electric pump.  Most of these carbs like a pressure of 6-7 psi from my exp.

[ACUDANUT]

Actually most carbs work better at 5 psi's.  I have had problems with my Holley's that have 7.5  psi's going into them. We all have different luck it seems, regardless of the carb and pump..

[tan top]

I'm using a Holley Red Pump.  I wonder what kind of shape the inside of the original return line is in.  Got any idea on prices for a new one. ? Thanks  

you can get shaped lines OEM style  , in plain steel  & stainless steel  ,  stainless is roughly double the price ,    if your car  , is not a stock etc , ( you have already a electric fuel pump ,  I would consider bending up your own vapour line  , from a reel of hard line below  ,  ( that what I done )   lot cheaper than a pre shaped line  , if your not going with a OEM resto  ,   second link  ,    I used copper line first easier to bend , to get the shapes ,  wernt sure how the stock fuel & vapour lines would fit round my added torque boxes &  2x2" x 1/4 " box frame connectors .  

 http://www.summitracing.com/int/search/part-type/tubing/tubing-material/steel?N=4294948076%2B4294949974&SortBy=BestKeywordMatch&SortOrder=Ascending&keyword=hard%20line


http://www.classicindustries.com/product/mopar/b-body-charger/parts/mf532a.html

http://www.summitracing.com/int/search/part-type/tubing/tubing-material/steel?N=4294948076%2B4294949974&SortBy=BestKeywordMatch&SortOrder=Ascending&keyword=hard%20line

[ACUDANUT]

The second option sounds right for me. Thanks

[303 Mopar]

I installed a Mallory 4110 pump on my '71 Challenger and it was very quiet.  I measured the 6.5-7 psi so I did not install a regulator to my Quick Fuel carb and it ran very strong.

http://www.summitracing.com/parts/maa-4110

[Charger-Bodie]

I installed a Mallory 4110 pump on my '71 Challenger and it was very quiet.  I measured the 6.5-7 psi so I did not install a regulator to my Quick Fuel carb and it ran very strong.

http://www.summitracing.com/parts/maa-4110

I have the same on my hemi.

[Jaysick]

I installed a Mallory 4110 pump on my '71 Challenger and it was very quiet.  I measured the 6.5-7 psi so I did not install a regulator to my Quick Fuel carb and it ran very strong.

http://www.summitracing.com/parts/maa-4110

Ive been wanting to get one but im worried about how loud it will be. 
Does anyone know how this compares to a holly red as far as noise goes? 

[303 Mopar]

I installed a Mallory 4110 pump on my '71 Challenger and it was very quiet.  I measured the 6.5-7 psi so I did not install a regulator to my Quick Fuel carb and it ran very strong.

http://www.summitracing.com/parts/maa-4110

Ive been wanting to get one but im worried about how loud it will be. 
Does anyone know how this compares to a holly red as far as noise goes? 

From the research I did, this was one of the quietest pumps on the market, including the Holley red.  On my Challenger, you actually had to go to the back of the car on the drivers side and be still to hear it.  I would not hesitate to buy this pump again.

[Charger-Bodie]

The Mallory is very quiet as far as electric pumps go.

[ACUDANUT]

The key to a quieter electrical pump is the thickness of the rubber against the frame. (less vibration)

[Charger-Bodie]

The key to a quieter electrical pump is the thickness of the rubber against the frame. (less vibration)

This is a very true statement. But the mallory ones are a different design (non-vane style i think) and is just quieter by desighn as well.

[firefighter3931]

The Mallory pumps are quieter due to the design as mentioned by Brian in the post above. The quieter operation is due to the gerator pump which is very similar to the rotors in a BB oil pump. The rotary vane pumps are noisier and more prone to cavitation than the gerator style. 

Big fan of the Mallory pumps here....I have the 250 GPH model in my car 

The 110 is an excellent street pump and can be run without a regulator deadheaded to the carb....and it's one of the quietest pumps out there 

The Holley pumps are not even close in terms of noise output 



Ron

[ACUDANUT]

Well, on a Holley, at least you can hear it working. 

[Jaysick]

The key to a quieter electrical pump is the thickness of the rubber against the frame. (less vibration)

This is a very true statement. But the mallory ones are a different design (non-vane style i think) and is just quieter by desighn as well.

Yeah this is what I was thinking too.  A lot of the bracket i see, look like the rubber around the ignition coil looking bracket is really thin.  The Mallory seems to come with a good looking bracket, really beefy looking.

[Jaysick]

The Mallory pumps are quieter due to the design as mentioned by Brian in the post above. The quieter operation is due to the gerator pump which is very similar to the rotors in a BB oil pump. The rotary vane pumps are noisier and more prone to cavitation than the gerator style.  

Big fan of the Mallory pumps here....I have the 250 GPH model in my car  

The 110 is an excellent street pump and can be run without a regulator deadheaded to the carb....and it's one of the quietest pumps out there  

The Holley pumps are not even close in terms of noise output  



Ron

Im not even gonna risk it.  The tinkerer in me wants to try and get a cheaper one and make it quieter but this technical explanation is enough.  When I go cheap I usually regret it..