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Discussion Starter #1
Will the 3/8 sending unit be able to handle being connected to an EFI fuel pump? It will be feeding an LT1 that needs around 38-45 psi of fuel pressure.
 

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Pump location? If it's in the tank then the flex(rubber) line will have to be changed to high pressure line and proper clamps. If the pump is in line then the stock hose will work, providing it's in good condition, since it's on the suction side of the pump. You will need a return line for the fuel coming from the return side of the regulator.
 

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Discussion Starter #4
I am planning on using the stock tank, with a OEM 3/8 sending unit, running through an inline pump. How would I modify the fuel system to use a return line?
 

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We have a 71 Nova that has a 87 350 cid using a electric fuel pump back by the tank.. I was told with the 4-7lbs of fuel pressure that this pump makes..we should not need a return line..?????? Inquiring minds need to know....

Rick
 

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EFI systems run in the range of 43 psi or higher if the need is there(lower for TBI systems).

You can run a return line to the fill tube that runs into the tank. There is a company that makes it easy with a piece that has a fitting attached and clamps on. You can make your own . Be sure the fuel entering the fill tube runs downward towards the tank. You can also remove the sending unit and make another hole in it for a return line. Solder the new line in with the fuel exiting away from the the inlet of the original fuel line pickup. Either way the soldering or welding is done away from the fuel tank for safety reasons. High pressure hose shouldn't be needed because the at this point the pressure is very litttle.
 

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http://store.summitracing.com/partdetail.asp?autofilter=1&part=MOR-65385&N=115&autoview=sku

You haven't mentioned fuel filters but a good method is a coarse(40 micron) filter before the pump(to keep the "trash" out of the pump) and a fine filter after the pump(10 micron) to keep the small trash out of the injectors. The first filter is for the safety of the pump and is optional but there should always be a filter before the fuel rail(injectors). An injector(s) can get clogged and lean out a piston(s). Filters should be rated to handle efi pressures.
 

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Discussion Starter #9
So a good fuel system for EFI would be sending unit, coarse filter, EFI pump, micron filter, to the engine bay, and then the return line plumbed from the regulator to the kit you have linked in your post. Sound about right?
 

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Yep. Sounds about right. The fuel pump may/should have a relay supplying the current. I found a pressure gauge on the regulator or somewhere on the pressure side of the system helpful but you can get away without it. Some regulators are adjustable and the gauge helps set that as well as being helpful in trouble shooting. One thing I should mention is that if the fuel pick up is picking up fuel like the stock pickup [carb(s)], then expect to run into fuel starvation in hard cornering or acceleration once the fuel level starts running low. The lower the fuel level the more the strarvation will show up. A sump or fuel resevoir in the tank will stop that.
 

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Discussion Starter #11
How would you go about putting a sump or reservoir into the tank? Weld it? Can I buy one pre-fabbed? Is it expensive to add a sump/reservoir?

By the way, thank you for answering all my questions quickly and completely. That is why I always turn to this board for answers before anywhere else.
 

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wannagofast said:
How would you go about putting a sump or reservoir into the tank? Weld it? Can I buy one pre-fabbed? Is it expensive to add a sump/reservoir?
I chose to buy a new tank and have a CE sump welded on. Check out my thread here for pictures:

http://stevesnovasite.com/forums/showthread.php?t=37780

The new tank was around $200, Sump was $61 and it was $50 to have i welded on. You can get a new sump with 1/2" NPT or with 3/8" NPT. I think there's a few fabricators out there making tanks with sumps welded to the factory style tank but they are a lot more expensive.

 

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I'm scratching my head on this one too. I have one of these sumps but I'm not sure I want to cut and weld my new tank.

http://store.summitracing.com/egnsearch.asp?Ntk=KeywordSearch&DDS=1&Ntt=gas+tank+sump&searchinresults=false&N=115&y=9&x=17

There are manufactuers that make bolt in tanks(Rock Valley comes to mind) if you're willing to pay for it. They do have a drop in fuel pump that goes in the top. I was thinking of doing something similar but still run the pump in-line. The stock look of the tank would still be there. The pickup doesn't need too much baffleing unless you're punishing the car in cornering or acceleration.

http://www.rockvalleyantiqueautoparts.com/catalog/tune_port_info_and_kits.pdf
 

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Discussion Starter #14
What would count as heavy acceleration? Would I be OK just leaving the stock stuff alone if I weren't planning on doing much more than a daily driver with an occasional trip down the track?
 

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wannagofast said:
How would you go about putting a sump or reservoir into the tank? Weld it? Can I buy one pre-fabbed? Is it expensive to add a sump/reservoir?

By the way, thank you for answering all my questions quickly and completely. That is why I always turn to this board for answers before anywhere else.
I JUST INSTALLED A 350 RAMJET IN MY 66 SS. I BOUGHT A FUEL TANK FROM CHEVY2ONLY THAT HAS THE PUMP ALREADY IN IT RUNS 45 PSI. YOU HAVE TO BUY THE NEW SENDING UNIT BUT, IT WORKS GREAT. BOLTS RIGHT IN JUST LIKE FACTORY IT JUST HAS ALL THE STUFF YOU NEED. TOO EASY. THIS WAY YOU DON'T HAVE TO RIG. I BELIEVE THE TANK AND SENDING UNIT IS MADE BY ROCK VALLEY ANTIQUES. THE COST FOR TANK AND SENDING UNIT WAS 650.00 / 700.00 BUT, IF YOU ADD UP THE COST OF A GOOD PUMP AND FILTER SYSTEM IT'S ABOUT THE SAME.:cool: :cool:
 

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I did a tbi conversion in my 69 chev C10 years ago. I used the mallory 60FI series external pump. this pump delivers a max of 55 psi. It was super quiet, and rebuildable. I drilled the sending unit and install a return that way. I never noticed any fuel starvation problems but the trucks have a different style of tank. I drove about 75 mile trip every day to work and after about 4 years I finally had to rebuild the pump (brushes worn out) the kit was under 15$. Summit has the pump for 145$.
 
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