I am looking at a LSX / LS3 engine swap. I want to run hard lines from the tank to the engine. I believe the LS motors have the fuel rails feed from the driver side of the motor.

Anyone have pictures of what you have done to feed fuel to the engine. Also what tank setup did you use. Mine corvette is a 78 so this is a 24gal tank.

Thanks....

 

I probably have pics somewhere, but not easily accessible right now.

You can put whatever fuel rail you like on there that will fit the manifold, the FAST system looks pretty modular, though I'd assume you want to cross over behind the intake manifold rather than in front.

I have two 6-AN PTFE lines running along the path the original lines ran, coming up near the starter and attaching to my throttle body (MSD Atomic TBI). I'm using an Aeromotive Phantom setup, with the bulkhead hole cut to the right of the factory sender opening. The system is using a Walbro 255 pump.

In words, the system looks like this:
AeroMotive bulkhead -> supply line long run -> fuel filter -> supply line short run -> TBI -> return line short run -> regulator -> return line long run -> Aeromotive Bulkhead

I also have couplers just off the fuel tank to make it easier to remove the tank if need be. I have to disconnect the fuel sending unit wire wire, the vent line clamp, fuel pump wiring and de-couple the two lines. I color coded the lines at the coupler IIRC. If not, I'll have a little bit of fun the next time I drop the tank.

 

So its a pref thing but if you not pulling the body hard lines are a PITA. I use the russel push PTFE lines, cheap, easy to work. I've used them for many different swaps in different cars and zero issues to date.

 

Now I would check Tanks Inc for their EFI tank. Then as said above -6 from the C5 FFR to the fuel rail.

 

Not an LS-but you get the idea!!!

Used the Russel -6AN lines teflon coated as well-

I wasn't that bad running them- w/o the body off- my knuckles weren't that torn up afterwards!!!

Did add a fuel cooler by Derale on the return.

Walbro pump in the tank using the hydramat

 

I've read you can flip the fuel rails to have inlet on passenger side. Something to look into.

I routed new Teflon coated ss braided flex hose from tank to the front but went down the drivers side. I had intentions on using the fuel rail covers. Stock tank with 82 sending unit with new pump for the ls3.

 

Stock tank from what year ? Is a 82 sending unit with a in tank efi pump ? do you have a part # for the unit ?

Something like this
https://www.summitracing.com/parts/h...model/corvette

 

1979 stock/ original tank. I bought an 82 vette sending unit and swapped the pump out. 82s came with a pump for the cross fire inj. You can get a pigtail connector for the wiring so it'll plug in just like a stock harness plus your have to run fp power. I don't have the part number on hand for the pump. I'd have to go digging through emails and emails.

That sending unit/ pump looks similar to the stock 82 setup. Looks like it'll meet the psi requirements for the ls (58-60psi i think, someone correct me if I'm wrong) and lph.

 

On my 71 body on, I ended up using poly fuel line from the firewall to the fuel filter regulator. Cunifer proved to time consuming and almost impossible to get over the rear frame, I didn't use braided AN to avoid that much rubber line. Poly is a PIA too.

 

Stock 3/8 line run side by side. Not accessible with body on

 

See my thread, i wrote instructions and have pics of how to do a LS swap fuel setup
https://www.corvetteforum.com/forums...part-list.html

 

Tag

 

Anyone try 1 of these
https://www.holley.com/products/fuel...s/parts/12-313

This installs into the factory tank, doesn't need a return fuel line (internal in the tank with regulator

Not sure how a LS3 engine likes this setup. Any reason to keep that standard fuel flow to engine fuel rails and back to the tank ?

 

Do some research. The return line is the optimum way to go

 

Yep- the reason newer cars are running a return-less system is to help evaporative emissions- and they are cheaper.

Controlling the pressure 8' away is not the best way to regulate the fuel at the rails/injectors.

Return systems are easier on fuel pumps as there isn't the surging associated with a dead head system. They actually keep the overall temperature of the fuel cooler as fuel waiting to be burned isn't sitting in the engine bay or fuel rails heat soaking.

The fuel that isn't used by the injectors gets sent back to the tank where it gets a chance to cool down before making the trip back up to the engine again.

Richard

 

Where is the best place to put the regulator.? close to the tank , or near the engine compartment so there is less fuel in the line heating up ?

 

Think of a returnless system as the government- you leave the pump -then stand in line till you get to see an injector- so if the car is idling- it could be a while....But you will eventually get to see the injector.

Managing the line - at the end of the line would be the least effective- closer to the front would be better. But if the line starts to move quickly- the pump has to play catch up. Not a real efficient design- hence- I named it government!!


Now a return style system- think of capitalism!

Everybody gets to run to the injector after they leave the pump. If the injector doesn't pick you- you run back to the end of the line. You get to try it again- running each time- doesn't matter if the injectors are at lunch idling- you are still running.

Yep - it costs more -but much better in the long run!!!

Richard

 

Well returnless cannot be that bad Its factory in my 2010 Corvette Grandsport (LS3) but is important as a on-demand system the pump operates as required. (varies) vs other systems which is on / off situation only.

 

This is where you want the regulator

 

Like I said- the returnless system works- it's cheaper and theoretically less gas vapor emissions.

But also remember- the factory put a lot of engineering in the returnless system to minimize heat soak- and using a PWM to control the pump

just google "ls swap heat soak"



For me- I was really impressed on how cool (temperature wise)my fuel lines are-

Regulator right here!!!