I'm taking my X1/9 from carburetted to fuel injected, so I need to create a new fuel delivery system. Here's the new tank (shown the way it sits in the car behind the driver) - it has feed and return ports at the bottom of the tank:
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Should I:
Option 1:
Fuel tank discharge (gravity feed) → Bosch 044 pump → filter → fuel rail → regulator → tank return
Option 2:
Fuel tank discharge (gravity feed) → low pressure pump (electric carb pump) → surge tank with Bosch 044 pump (plus return to tank) → filter → fuel rail → regulator → surge tank return
I'm leaning toward using a tank that the 044 pump sits in partially submerged like this (~$50 on ebay):
Option 1 is a little cheaper, but I'm concerned about fuel starvation at low tank levels. Option two is obviously more complicated, but that's where you come in. $100 extra isn't a big concern, but I need a reality check to see if the surge tank is needed here.
If you weren't using an EFI tank, I'd see where the surge tank would be nearly critical.
That EFI tank seems pretty awesome compared to most of the flat tanks in use elsewhere.
If you're that concerned, you could use some of that Holley pickup mat stuff to reduce the chances of fuel slosh being an issue.
The Exxie engine bay isn't exactly the roomiest, so finding room for another tank might be difficult without essentially building one from scratch.
Whenever possible I use an in tank pump. This looks like one of those time to me. You've got a brand new tank. Mod it however you need to in order to get a pump in there.
The fuel injected X19 tanks had a makeshift surge tank built into the pickup/return area from the factory. Even at very low fuel levels mine never had starvation issues. As long as the Bosch 044 is mounted low enough (like the injected X19s were). there should not be any problems whatsoever with option #1.
stafford1500 said:
The fuel injected X19 tanks had a makeshift surge tank built into the pickup/return area from the factory. Even at very low fuel levels mine never had starvation issues. As long as the Bosch 044 is mounted low enough (like the injected X19s were). there should not be any problems whatsoever with option #1.
Was just gonna ask if there are any baffles in the tank or if they could be added, a baffled tank is the best setup overall - simple, cheap, and effective.
Stefan said:
If you're that concerned and not on a tight budget, you could use some of that Holley pickup mat stuff to reduce the chances of fuel slosh being an issue.
FTFY...that stuff is so expensive, it'll make you wish you only had to cover the expense of a surge tank setup. Their cheapest and smallest mat, possibly meant for a kart (or RC plane?), is $140, and the cheapest one that might be of use in a production car is $200.
The solution I use is keeping the tank at least half full in competition. This also helps keep the in-tank pump cool, but the downside is that it's a bit heavy.
GameboyRMH said:
FTFY...that stuff is so expensive, it'll make you wish you only had to cover the expense of a surge tank setup. Their cheapest and smallest mat, possibly meant for a kart (or RC plane?), is $140, and the cheapest one that might be of use in a production car is $200.
The solution I use is keeping the tank at least half full in competition. This also helps keep the in-tank pump cool, but the downside is that it's a bit heavy.
Wow. It's that much?! 
Yes, the tank has a baffled section. Here's a pic:
Looks like the baffle is only open on the forward edge. The left side appears to be pretty tight to the tank wall.
Thanks for the input Stafford - that's just the sort of data I need. I should have mentioned that I have no idea how the FI X1/9s were plumbed.
You may want to look into a Holley Hydramat. I ditched my surge tank setup on the S2000 in favor of adding that to the bottom of the pump and I can essentially run it dry before I fuel starve!
That baffling should be good to 1/4 tank on slicks, 1/8 on sticky street tires. Thats assuming maximum lateral force.
Mount the 044 low (personally I prefer an e2000), feed it with the biggest line you can, 3/8 to the rail, 5/16 return to the tank. If you want to get crazy, theres some bronco company essentially making a combination surge tank/fuel filter that'll give you about a quart. But you dont need it.
I made one for pocket change with some 2" water pipe and some 5/16 fuel line and pipe thread fittings. I calculated its capacity as 700ml.
Underside of the car looks kind of like a moonshine rig but it doesn't fuel starve anymore.
Whatever route you go, figure out the price on all the fittings, pumps, regulators, gauges, etc. By the time I priced out everything to do the inline high pressure pump and regulator, I decided to just go with a FiTech fuel command center. Everything needed in one cool looking package.
