Squarebody gas tanks?

[Factory Guy]

When converting to an LS I have heard for the squarebody's you just get a 1987 Square body tank, since it already has the baffle in it for Fuel injection. So I thought, great, I will just get one of those. Now I am reading mixed reviews on how well it works. Many guys are saying with the power of the
LS, they still have problems with the engine running out of fuel if you step on the gas, hard, and the fuel level is low even with the "extra tray" in the 1987 tank?

Thoughts??

[mongocanfly]

My 81 has no baffles...I've never had a issue...

[ls1nova71]

The baffles will definitely help, even if not as well as a newer vehicle with a fuel bucket type sender. On the other hand, if you keep the tank relatively full all the time you wouldn't need them. My Nova doesnt have any baffles in the tank, but does have a small sump on the bottom and even with that, taking off fast with a low tank will make it fall on its face for a second, really wierd feeling the first time it happens!

Also a '73 wont have a big enough opening to put the 87 sender in so you can have an intank pump. New tanks aren't all that much, small price to pay to make it simple. May have to come up with an adapter for the filler though as I believe they are different sizes, although not positive about it.

[Wgesnerjr]

I put an 87 "baffled" tank in my 85 during the LS swap. The tank is the same but has a "sump" welded to the floor that the sender sits in. (looks like a pan you bake bread in from the kitchen-its about 3-4 inches deep) The attached pics were shot through the sender unit hole and the filler neck hole. On each side you can see a "raised up" part on the floor of the sump. There is a hole where gas can enter and leave.

I have not had any problems with fuel starvation in the 1+ years I have been driving. I let the gas get low but not enough to make the needle stop moving. So there is always something sloshing around. Also, I do not drag race it but have done a few quick starts from a red light with no issues. If you keep it above 1/4 full, there should be no problem.

[verdell]

The non-baffled tank isn't necessarily a deal breaker but if I were doing it, I'd go ahead and get the fuel injected tank. I originally had a non baffled tank when I first installed my 5.3. I think perhaps there was an issue with my fuel sender that gave me an incorrect fuel level reading. Long story short, low level fuel sloshed and I ended up having to replace the pump. I took that opportunity to replace the fuel sending unit, re-did the grounds and replaced the tank with baffled or TBI tank. The built in pan is just added piece of mind for me, I guess. We've done about 5 C10 square body swaps and put '87 tanks, '87 sending unit and EP381 fuel pumps in all of them with no issues.