hi does any one know for sure if a grand natiaonl fuel sending unit will work in a elcamino fuel tank ?

The GN, Monte, Malibu, gas tanks are all about the same. I just put a 5th gen Elky sending unit next to a Monte unit. To answer your question, yes it will "work". But, will it allow you to use all the gas in the tank? No. Will the fuel gauge read correctly? No. The tube for the pickup sock, and the float arm are longer and a slightly different angle on the El Camino sending unit.

But in a pinch you could probably use the GN sending unit. :-P

this sending unit would be for a 78-87 elcamino . i think u have an idea of what i am trying to do . geting a gn unit with a fuel pump on it .
i have seen a crabed unit out of a elcamino but never a F.I unit . once i find a F.I. unit i will buy a new elcamino tank with the baffels ect. does any one know what a 87 elcamino F.i. sending unit looks like ?

thanks chad

This is a pic of a 87 22 gallon tank sender for an El Camino http://198.208.187.182/internet/PartImage.jsp?mfgname=ACDELCO&prodlinecd=43&acpartnbr=25092938

this is a pic of a 87 monte carlo sender
http://198.208.187.182/internet/PartImage.jsp?mfgname=ACDELCO&prodlinecd=43&acpartnbr=25092742

Does anyone know what the difference between the 85-86 el camino 22 gallon sender PN 25004940 and the 87 el camino 22 gallon sender PN 25092938 is? the 87 sender is still available but the 85-86 is not.
Also does anyone have the dimensions for a 22 gallon el camino sender (length of tubes, position of electric sending unit, length of float arm). cant find a used sender so I am thinking of rebending/ lengthning a monte sender.

G-Body, did you get your sender installed? Did you find the correct sender of modify one?

I ended up finding a used sender from a 87 El Camino. My El Camino is up and running with a 2001 5.3L 4L60E and a 3.73 GN rear end. That LS1 is great, sooooo glad I put it in there, way more power than the 305 and better fuel economy :D. 14.00@97 and 20MPG.........not at the same time though.

Is there a difference between the carbed sending unit and the EFI sending unit? If so, could someone explain it to me? I'm looking to buy an EFI tank and would like to have a matching sending unit. There is an aftermarket company offering tanks and units and I want to make sure that I get the right items. I plan on transplanting a GN drivetrain into my 85 Elky which currently is carbed. Thanks

Yes there is a difference. The FI unit is designed to have the stock fuel pump inside the tank. It has the bracket for the pump and a place for a fuel return and vent. The gas is dumped down a tube to the bottom of the tank.

The carb unit has just two hoses. One for feed and one vent. You can modify a carb sending unit to have a third line for the return fuel. You will have to have an external pump if you use a carb sending unit. I tried an external pump for about a year but I hated the constant whine of the pump. I went ahead and put in a 22 gallon fuel injection style tank, sender and pump. The fuel injection sending unit was the most expensive part of the entire upgrade.

Your stock carb tank will work but as you get to about 1/3 of a tank of gas you will get fuel starvation in hard turns. The fuel injection baffle in the tank is like a sauce pan with a 1/2 inch hole in the bottom. The "sauce pan" has little feet so it is not right on the bottom of the tank.

If you don't end up with a genuine GM or OEM tank do yourself a BIG favor and add a filler vent tube before you ever put it on the vehicle.

Check the thread titled LT-1 Tank upgrades. Good Luck.

Thanks for the info. I will definitely add a filler vent tube.