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280Z stock fuel tank with LS-1 for dummies


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Hey All, I hate to be the guy that seems like he's not using the forum search, but I really have tried and just can't piece together a complete, easy to follow solution for someone like me with very little experience.

 

I am starting with a running, stock '77 280z (EFI) and swapping in an LS-1 from a stock '02 firebird, stock fuel rail. I should state that I am not looking to take this car to the track, I would like it to be a reliable daily summer car. So my priorities for the setup lean more towards ease of diagnosis and keeping the engine bay looking clean, rather than ultimate performance.

 

I am looking for a complete list of parts I need to get, and where they go, to finalize the fuel setup.

 

I have tried to sift through as many threads as I can, but it seems like one portion or another is always generalized or assumed. This is my first time, so I need some hand-holding :(

 

Here's is where I'm at:

I have already removed the L28, and mounted the LS-1, following instructions provided with the JCI mount kit. If I understand correctly, this means I currently have 2 hard lines coming from the rear of the car. The first is currently going from the tank, through original fuel pump, fuel damper, then to the engine bay. The second is the return and it goes directly from the bay to the tank.

 

Here's the general setup I have been able to piece together from different threads:


  1.  
  2. Keep the stock 280z fuel tank, as it is already setup for fuel injection.
  3. Add a fuel filter between the tank and new pump, to protect the pump.
  4. Replace the stock fuel pump with a higher flow pump.
  5. Keep the stock hardline going from the pump to the bay.
  6. Run this line to a fuel pressure regulator, preferably with a guage. The regulator will have 3 line connected to it:
    ⃠The line coming from the pump.
    ⃠The other (return) hardline
    ⃠A line going directly to the stock LS-1 fuel rail
  7. Another fuel filter somewhere?
     

So assuming that setup is somewhat accurate, here are the questions I have in order to make it more specific and more of a step-by-step process:


  •  
  • A. What fuel filter should I use for step #2?
  • B. What new parts specifically (lines, fittings, etc) do I need to add this fuel filter?
  • C. Is this filter something that needs to be mounted? If so, how?
  • D. Which new pump should I use? I have seen 2 main options:
    ⃠Walbro GSL392 255 lph (http://www.summitracing.com/parts/VPN-GSL392/) Would I need any extra parts for mounting?
    ⃠He doesn't give any part specifics, but the high flow pump provided by JCI.
  • E. What fuel pressure regulator specifically should I use? People seem to mention Aeromotive a lot but there are so many options.
  • F. What new parts specifically (lines, fittings, etc) do I need to complete the 3 connections the pressure regulator will involve.
  • G. Is there any generally accepted place/way to mount this regulator? Is there an existing bracket or something I can purchase?
  • H. Do I need a second filter? If so where, specifically what part, and where does it go?
  • I. Do I leave the stock fuel damper in the setup?
  • J. The JCI instructions mention re-routing the lines to go straight up the firewall. How is this accomplished? Can the hard lines be bent in some way?
  • K. Some have mentioned flipping the LS-1 fuel rail. Is this a good idea and what does it accomplish?
     

 

This is a side note, but it may have some impact on the fuel setup. After reading around it seemed everyone had a better opinion of the transmission mount from JTR rather than JCI, so I went with the JTR mount. However it seems it will interfere with the stock placement of the fuel/brake lines. (pics) What is the recommended way to remedy this?

 

post-9082-088653600 1295116716_thumb.jpg

post-9082-052327100 1295116733_thumb.jpg

post-9082-089863700 1295116747_thumb.jpg

 

Thanks in advance to anyone willing to help. I know it takes extra effort to provide specific info, and it is much appreciated.

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I have a stock LS1 fuel rail with a -6AN fitting welded onto it instead of the GM quick connect fitting. I am changing my fuel set up to fuel rails. If you are interested you can buy the fuel rail that I'm removing from the car... if interested PM me.

 

Fuel pump I'm running is the Aeromotive A1000 (overkill by many ppl standards, loud too, but it works). I'm running new braided lines (feed and return) with all -AN fittings and bypassed ALL stock lines. I mounted my regulator by the fusable links in the engine bay, I'm using this: http://aeromotiveinc.com/products-page/regulators/efi-regulators/13101-a1000-injected-bypass-regulator/ regulator (aeromotive). I am running an Aeromotive 10micron (i think 10 micron off hand) fuel filter inline as well.

 

So my setup is -10 line to pump, -8 line to regulator -6line to rail and a -6line return

 

in the attached pic you can see the regulator and fuel lines on the passanger side and the fuel line that is running across the intake manifold.

post-3124-080956400 1295119069_thumb.jpg

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I am at about the same stage where you are but with an LS2. I am modifying a 240z tank to mimic a 280 tank to limit chassis fabrication and fuel guage trouble. I am having a re-sealable service access port put in it to be able to open it and clean it out if it gets dirty (again) or if I need to add and change fuel cell foam. I will use 3/8" hard line thru the stock fuel line blocks on my 240z which runs thru the trans tunnel (not as convenient as 280z which is on floor pan). Your lines look good, I would use them. I have talked to guys running the stock sized 280z hard lines without any trouble. The reason some guys flip the fuel rail is to switch which side of the car the inlet is on. I plan to have AN6 fittings welded on my fuel lines and only use flex lines for short sections. There is a local hose shop in my town that will braze/weld them for me and make my flex lines to order. I will mount my Walbro 255, a corvette fuel regulator/filter after the pump, and a see-thru filter between my tank and my pump. All of this will be mounted on a plate bolted to my tank. I don't think I will need any other regulator beyond the corvette filter/regular (anybody?). So I only plan to run a single 3/8 line up to my engine. The 5/16 return line will be short, just running from the filter/regulator back into the tank. No return from engine bay, since regulator is in back. Speedway Motors has an MSD fuel pump, corvette regulator and fuel fitting package that is priced cheaper all together than you can buy the individual pieces. I thought about putting a fuel filter sock on my pickup inside the tank, but then I can't service it without dropping tank if it gets dirty. No one likes see-thru filters, but it is on suction side of pump so in my mind it won't see high pressures. For the trans mount, I would just chop it off and drill new holes. I welcome feedback on my plan from the forum because I haven't done it yet.

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I am at about the same stage where you are but with an LS2. I am modifying a 240z tank to mimic a 280 tank to limit chassis fabrication and fuel guage trouble. I am having a re-sealable service access port put in it to be able to open it and clean it out if it gets dirty (again) or if I need to add and change fuel cell foam.

 

Do you have a thread about your tank modifications? I don't want to thread-jack but I would be interested in hearing more about how you adapted the 240 tank for fuel injection.

 

And why not just use a 280z tank instead? Is it that much more difficult to swap one in place?

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I am finishing up my fuel system today.

 

3/8" aluminum hard lines replaced the stock hard lines.

The hard lines are connected to steel braided lines which connect from the pump to the tank and from the the lines to the FPR and rail

 

Feed line is connected to the right fuel rail

Right fuel rail has a line across the front to connect to the left rail

Aeromotive FPR is connected directly to the rear of the driver rail

Return comes off the FPR and back to the tank

I used after-market solid fuel rails (forget the brand)

Pump is a Walbro 255 with an inline filter mounted in the rear

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I had similar plans with my car and weighted the same options. If youre going with the "simple, clean engine bay look" but only plan on running a stock LS engine I wouldn't bother with the more expensive aeromotive stuff and fancy fittings. Here is what I recommend doing:

-Flip the fuel rail so the inlet is on the passenger side. Since the stock lines run on the passenger side of the car this keeps you from having more hoses or lines in the engine bay.

 

-Mount the walbro 255 lph pump in or near the stock location and the corvette FPR (ac delco number gf822) in the rear of the car. Putting the FPR in the rear lets you run only 1 fuel line up to the engine.

 

-When I did it I took off my stock fuel lines and bought a length 3/8 fuel line. I carefully hand bent the 3/8 line, taking measurements to make sure it was a close match for my hard lines except for one difference. Instead of following how the stock lines run once they are in the engine bay I simply bent the line straight up so it ran up the firewall. You can see it here (its the thick fuel line that just kind of stops at the battery tray area):

P1040599.jpg

Alternatively you can use the 280z main fuel line (I believe its 5/16, I remember reading it should be juuust enough to feed a stock LS1).

 

-The rest is easy. I used a 90 degree quick connect fitting (dorman #800-059) to go from the fuel rail to the 3/8 line and used more dorman quick connect fittings on the FPR (#800-155 fuel rail outlet, #800-121 3/8 inlet, #800-120 5/16 outlet). I used standard 3/8" and 5/16" fuel injection hose and fuel injection hose clamps where appropriate for connecting everything together. For a fuel filter I just went to napa and asked for one with 3/8" ports that was good for fuel injection pressures. This setup seems to hold pressure and give the engine plenty of fuel.

 

Everything works great, the fuel system has been flawless so far with 1000+ miles on the swap. What was nice too was that everything was very cheap and can be found at pretty much any auto parts store if I ever have to replace anything. It also keeps more "stuff" out of the engine bay.

P1040622.jpg

P1040621.jpg

Edited by h4nsm0l3m4n
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Thanks everyone for the more detailed info.

 

h4, your setup looks especially easy and clean, and thanks for the specific part numbers and such. I think this method may also solve my tranny mount interference issue as well. Do you have any pics of the components in the rear? With your setup did you eliminate the other stock component next to the stock fuel pump, some diagrams have this labeled fuel dampener? Does flipping the stock fuel rail still allow the use of stock (or similar) corvette rail/injector covers? The fuel filter you mentioned asking Napa for, does that go between the tank and the pump?

 

Along with the stock brake, fuel feed, and fuel return lines, there is a 4th line running to above the fuel tank. I am assuming this is some sort of vent/vacuum line? What should be done with this? Can it be eliminated?

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h4, your setup looks especially easy and clean, and thanks for the specific part numbers and such. I think this method may also solve my tranny mount interference issue as well. Do you have any pics of the components in the rear? With your setup did you eliminate the other stock component next to the stock fuel pump, some diagrams have this labeled fuel dampener? Does flipping the stock fuel rail still allow the use of stock (or similar) corvette rail/injector covers? The fuel filter you mentioned asking Napa for, does that go between the tank and the pump?

 

If I understand your pictures correctly, you received the wrong tranny mount. The 280z bodies (and late 260z bodies) have slightly different floors and frame rails. The tranny mount you have is for a 240z which bolts up through the floor of the car. The later 280z mount has flanges on the side which bolt to the frame frails horizontally like this:

IMG_0122.JPG (pic off of www.4moores.com)

With this style mount you shouldnt have any clearance issues. If this is the case get a hold of John and have him send you the correct part in exchange.

 

As far as the "fuel dampener" I'm afraid I cant help you much. My car used carbs so I did not have most of the fuel injection stuff yours probably does. I also had to run a surge tank since I had an unbaffled tank and plan to race the car. If I had to guess I'd say you can remove most/all of the fuel related components and run your own stuff without too much worry (thats what pretty much everyone I've seen does). My napa filter is indeed between the pump and the tank, the corvette FPR is also a secondary fuel filter.

 

I'm afraid I'm not certain about corvette fuel rail covers since I personally dont run them. I think youd probably have to modify the passenger side cover to allow the fuel fitting to fit but you may be able to tuck it underneath and run the line out the back. Please post what you end up doing for this since I hope to add fuel rail covers sometime soon...

Edited by h4nsm0l3m4n
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Thanks again all :)

 

I think I'm almost there. I made a quick diagram to see if I'm understanding h4's setup correctly.

 

post-9082-005918300 1295326383_thumb.jpg

 

A few questions:

 

1. The pic/description on summit racing for the pump is confusing me. (http://www.summitracing.com/parts/VPN-GSL392/) It clearly says threaded 10mm x 1.0 for both inlet and outlet, but in the pic I feel like I can clearly see a nipple end. What connectors exactly do I need to finalize my diagram?

 

2. Is it fine to use normal rubber fuel injection hose + clamp to connect to a hardline that does not have a nipple? For instance in the case h4 mentioned where his new hardline ends in the bay, I'm assuming this is just a clean cut smooth end. Or in the case of the connector coming out of the corvette regulator to the rail...

 

3. What would be the easiest/correct way to cap/eliminate the vent on the tank?

 

Thanks again!

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For the pump youd need 10x1.0 mm to 3/8" hose nipples, I dont think the picture there is correct. I bought this nice kit from DIYautotune for the fittings, etc. http://www.diyautotune.com/catalog/walbro-gsl392-full-installation-kit-400939-p-313.html

 

For the fuel fittings, I did not clamp the hose over a straight fuel line. I single flared the end of it using a tube flaring tool, slipped on the hose (it was very tight fit over the flare) and tightened using the hose clamps.

Edited by h4nsm0l3m4n
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Guys - My car is the 280Z that JCI used to develop their kit. I worked with John for about 14 months to get the conversion done and refined. I basically have all the components he currently sells except for the transmission mount. Mine has a prototype torque tube style set-up that he decided would be too complicated for most people. If you have questions about locations, etc. I can take photos of what has been done on my car and send it to you. Email me directly.

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  • 3 weeks later...

Ok awesome.

 

Also I realized I didn't include the filter before the pump in the diagram. I'll have to add that tonight along with the fittings.

 

If you ever updated your diagram, I am trying to confirm the various fittings by and between the components - I have the FPR, the filter and the pump.

 

Seperately, in a 240Z, can I use the stock hard line from the FPR to the rails? Seems I would need to step down the FPR from a 3/8 to 5/16 to match the hard lines if I did this, but the other option is paying hundreds of dollars for a new 3/8 hard line, when the 5/16 should be sufficient for LS1 power.

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I am using the stock 73 240z tank as well but I have welded on a sump to my tank. Were I’m stuck right now is, where to connect the vent line? I was thinking of routing it to the filler outlet and removing the expansion tank, see first diagram. Second diagram shows were I would like to put the vent line, with the expansion tank removed. Will this allow the tank to breath and keep enough pressure in the tank?

post-983-039641500 1297546146_thumb.jpg

post-983-077714500 1297546155_thumb.jpg

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I am using the stock 73 240z tank as well but I have welded on a sump to my tank. Were I’m stuck right now is, where to connect the vent line? I was thinking of routing it to the filler outlet and removing the expansion tank, see first diagram. Second diagram shows were I would like to put the vent line, with the expansion tank removed. Will this allow the tank to breath and keep enough pressure in the tank?

 

Why do you want to eliminate the expansion tank?!!!

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