well, you could use your existing pump to feed the surge tank, but then you'd need a separate pump either in the surge tank or outside to feed the engine.

I'm wondering if the surge tank couldn't be incorporated into the main gas tank itself; wall off a 1-2 gallon area that's completely sealed separately other than a cutout at the very top for fuel to go back into the rest of the tank once full. Use an in-tank small pump to feed this area, then another in-tank or external pump to feed the engine as normal. The engine pump would feed from and bypass to the sealed off internal surge tank.

The simplest solution in your case that wouldn't cost any money is to simply keep the tank full. Once it gets down approaching half a tank or so, just fill up. The added benefit is that the total at the pump would be lower..................... :yes:

Jody

Just a Question, Why would we be having problems with the EFI and Starving for fuel if the factor LS1 in a camaro or trans am or corvette never had this problem?

Because their engineers designed the tanks properly.

Which brings up another question....why wouldn't the aftermarket tank manufacturers just dissect a factory tank and copy the layout?

most of the late model stuff uses a pump housed in a bucket, with a venturi setup for return and pump feed; they can go very low without any issues. You can upgrade to the larger 255 lph Walbro and similar pump, and should be able to get one in an aftermarket tank.

Won't help the big power guys who need much larger or twin pumps; in their case a simple surge tank is the easiest way out.

Jody

Good stuff, Jody.

This looks like a great cost effective way to alleviate this issue should I have them when I am done.

Thanks for chiming in.

thanks, too bad it has been a stalled project for way too long, I quess I shouldn't have gotten sidetracked on too many other things. eh...oh well.

wonder if someone could come up with a deal like bmw uses in its factory tanks, with the tanks mounted under the back seat it is a "saddle bag" style with a hump in the middle for the driveshaft. the only pump in the tank is in the rh saddle and they use what they call a "siphon jet" pump that siphons fuel from the lh side of the tank when the fuel is returned by the return fuel system it will suck the lh saddle pretty much dry. I wonder if a similar setup could be used to feed the "surge" tank inside the main fuel tank as jody describes.

okay, you've peeked my interest.

So i searched the net and couldn't find anything on the BMW tank. Any chance you have a link or pictures.

I don't have a pic of an actual siphon jet pump out of a tank, I'm not sure if i can get one until a fuel tank has to be replaced at work then I might be able to get the line out of the tank with the siphon jet pump out of it.

I only have a training manual with a drawing of the siphon jet pump itself that I can take a pic of or something. not sure if it will be of any use, I will try to find an online drawing in the next few days.

i did a search for "siphon jet pump" on google and came up with this link apparently gm has been using similar stuff for a while now too. this link kinda shows where it is in the tank and you can get an idea how it works, now getting ahold of one will be the trick.

I did a search on google hoping to find a siphon jet pump of some sort that could be easily used on somthing like this but i got tired of looking at web pages.

hope this helps.

http://www.hessh.de/Corvette/FuelTankSystem.pdf

i talked the the parts guys today and they have a tank that was replaced and bmw doesn't want it back so it is going in the trash, I will be getting it tomorrow to get the siphon jet pump out of it, so syborg tt if you want it to experiment with I will mail it to you. just let me know address etc....