EFI with factory Fuel Tank??

[Grip]

Check out Z10's build. http://67-72chevytrucks.com/vboard/s...=1#post6356218

He made a surge tank that is fed by the engine mounted fuel pump. The surge tank holds the in-tank high pressure fuel pump from the same make/model as the engine. The return returns to the surge tank so the stock fuel sender is un-modified. The surge tank is mounted under the hood so the electric fuel pump is further away from the cab.

[no1udknow]

I haven't read through all the posts, but the old tank that was in the truck when you got it worked, minus the jb weld leaks, why couldn't you find another stock tank, and modify it the right way. Tap into it the right way by soldering in the pickup and return lines. I have done it to a few motorcycle tanks, but the other way around. I have taken some EFI tanks and welded shut the big square holes where the pump used to sit, and then tapped and soldered in a bung for a screw on petcock on the side of the tank. If you can think it up, it can be done.

[stevencvn72]

Originally Posted by no1udknow

I haven't read through all the posts, but the old tank that was in the truck when you got it worked, minus the jb weld leaks, why couldn't you find another stock tank, and modify it the right way. Tap into it the right way by soldering in the pickup and return lines. I have done it to a few motorcycle tanks, but the other way around. I have taken some EFI tanks and welded shut the big square holes where the pump used to sit, and then tapped and soldered in a bung for a screw on petcock on the side of the tank. If you can think it up, it can be done.

I didn't like the locations of the jb welded pick up and return lines. They were at opposite ends of the tank at the bottom and caused cavitation on the reg. Center pick up seemed like it made more sense. However, simply welding bungs at the bottom center of the tank would make sense, but it seems like all the debris in the tank would eventually cause an issue compared to pulling fuel up out of the tank.

[thumpros@yahoo.com]

I'm fairly new to this forum also. I have the 68 C10 SWB and everything is frame off at this time. I want to start building the fuel system to feed the 5.3 LS EFI engine.I jumped in on this forum late. I keep seeing "Blazer" gas tank referenced.What year, body trim blazer?

This is an awesome website and this discussion is helping me develop my fuel system ideas. Thanks everyone!

[LockDoc]

Originally Posted by thumpros@yahoo.com

I'm fairly new to this forum also. I have the 68 C10 SWB and everything is frame off at this time. I want to start building the fuel system to feed the 5.3 LS EFI engine.I jumped in on this forum late. I keep seeing "Blazer" gas tank referenced.What year, body trim blazer?

This is an awesome website and this discussion is helping me develop my fuel system ideas. Thanks everyone!

Be sure and check out the "LS Swaps" Forum too....

LockDoc

[cerial]

I am going the other way and putting a 72 tank into my 87 and came across this thread.

Here is my plan for the vent line routing;
Put a cap on the sending unit plugging that line.
Have the two ports on the drivers side connected with a brass T in between them
Have the passenger run over to the drivers side into the middle of a 2nd t that connects to the first (lower) T.

Then I have a line running all the way from the (Upper) T to the passenger side then the line does a 90 and goes up inside the B pillar then down before coming back and folling the fuel line through the floor and inside the frame rail to the 87's evap.

This should allow the truck to be on it's side or roof and little to no fuel to enter the evap line thanks to gravity.





For the fuel line I have something that seems like it should work.

I have the return line running to A high pressure T fitting with the tank feeding into the top of the T and the pump feeding from the bottom of the T. Now the circulating of fuel from the return back to the pump should siphon fuel from the tank and only as needed.

If I run the pickup dry then cavitation could happen but will resolve itself as the bubbles either return to the tank or are pulsed into the tbi creating a momentary lean.

I believe I will need to prime the system the first time. But once primed as lone as I don't run completely out Of fuel this should keep siphoning fuel from the tank into the loop and not require a second pump.

The pump will be pushing fuel. But as the T is above the pump any return fuel will be pushed against the backside of the pump so the "pulling" will be minimal. I am thinking it should gravity siphon and keep the loop full and when running the thing should find a psi where it will stop pulling fuel from the tank to keep the loop full . If I go hard throttle to nothing a surge may be sent back into the tank. But once back on the throttle it should continue to siphon and not be an issue.

Or I could be horribly wrong and only make it a mile and the thing starts to sputter.



Plan B is to just do the idea of taking it to a radiator shop and doing the 3 ports on the bottom of the tank to gravity feed into the pump. That being said I don't want to modify a bran new tank if I don't need to.

[cerial]

Decided I am going to take it to a radiator or welding shop and have them braze 3 bungs into the bottom.

I am almost confident enough to braze it myself. But figure the cost in materials will be around 1/2 what a shop will charge and were talking gas so they can take my cash for the professional outcome.

Use the same T return as before. Just have the 3 feeds going into 1 above the T

The pre pump filter will catch anything big. I am pretty good about maintenance and the filters are only around $10-$20. I could clamp the 250psi rated rubber line if I need to install a new pump or filter in a parking lot.

[bMr]

The OP started this thread in 2009 and things move on. Holley's Hyrdamat has since been released and may be of interest to those needing to utilize a stock tank.

https://www.holley.com/products/fuel_systems/hydramat/

[MARKDTN]

cerial-why not use an '87 factory TBI tank with the pump in the tank and a baffle and everything? It's a bolt-in to all 73-87s. Why reinvent the wheel?

[cerial]

Originally Posted by MARKDTN

cerial-why not use an '87 factory TBI tank with the pump in the tank and a baffle and everything? It's a bolt-in to all 73-87s. Why reinvent the wheel?

Yeah it has fought me a bit but is in therw and will come out easily.

The saddle tanks sit to low and a rear tank requires a heavy skid plate which traps dirt and rust the tank.

An in cab tank eliminates issues with clearance, rust, and in my case snow sitting on the tank. Also safer location with current headache bar and later inside roll cage.

Trying to not have anything custom. But the 3 ports makes sense to save the pump and keep it quieter.