• Hello Guest, welcome to the initial stages of our new platform!
    You can find some additional information about where we are in the process of migrating the board and setting up our new software here

    Thank you for being a part of our community!

Show me how you are fueling your LSx cars!

2turbotoys

Salaminizer
Joined
Nov 13, 2007
Location
Reading pa
I have been going over options to get enough fuel to my L33, I would like to do it right the first time. Goals are: 1st get it running N/A (currently dynoed at 450 hp) 2: Have enough fueling capacity for twin turbos.

Originally my idea was to modify the stock sender, maybe chop off the ports and install A/N bulkhead fittings. After looking at my new sending unit, it seems its too much of a piece of crap to put that much work into.

I then looked at mounting a fuel cell under the car in the stock tank location, with the intent of using the stock filler cap. Figuring that out is proving to be pretty difficult, I haven't found a cell with the filler on the side or even on the top close to where it needs to be. I don't really want to fill the tank through the trunk because I want to use this car, and occasionally I fill the trunk with groceries, antiques, her thrift shop finds, etc.

Another idea was to use the stock tank and sending unit, then cut another hole in the top to use this: http://fuelab.com/inventory/item/20901___fuelab___in_tank_power_module_install_kit/
which basically provides a fuel pump mount location with -8 output fitting. This requires using their pump (not a problem) and using the stock return line.

What do you guys think? What did you do?
 
I grafted a subaru fuel pump lid on the stock tank which allowed me to use two walbro 450 in-tank pumps and the stock sending unit. Another option I would consider is adding a sump to the stock tank and running a pair of external AEM 044 copies. They have proven to be reliable in a turbo ls car I build that sees daily driver duty. I would always opt for the in tank option but either way its only 300 bucks worth of fuel pumps, even a single of either might get your power goals on gas. Most important part is good relays and wiring so you get full alternator voltage to the pumps.
 
Who makes the best relays? I have had problems with every newer relay I've bought, I even had to switch my efan back to an original Volvo relay. I agree with the in tank pump, but Walbro, idk about the reliability, from what I've gathered they don't make the best stuff. There is a million ways to ensure voltage at least, like a big ass capacitor. Budget isn't a huge problem with this build. Why a sump? Are the pumps extra large? I'm in uncharted territory (for me) so forgive the questions, thanks!
 
I like to use the bosch/tyco 75 amp relays. I think the bad walbro stuff comes from people buying fake copies off ebay, I've never had an issue with a real walbro, but maybe I'm just lucky. Any external fuel pump will need a fuel sump on the bottom of the tank to keep the pumps fed, basically a low point for the fuel to collect as it gets sloshed around form driving. If you look inside a stock tank it has a factory "bucket" welded in that the pump draws from. Another option in a small in tank feeding a surge tank. It's really common for people to undersize relays and wire size and only end up with 10 volts at the pump. If you look at the flow charts for either pumps, the flow really nose dives as voltage drops.
 
I've seen those charts with fuel pumps, this is a weird comparison but back when I used to build big car audio systems, it was the same problem with voltage. Running amplifiers at very low ohms really needs full voltage, 14.5 VDC if possible. I have an old school Orion dual battery voltage regulator which ensures 14.5 V output, I will probably use a similar, more modern unit, or a big capacitor.

55superbeetle, your choice was closest to my 3rd option, cutting a hole in the stock tank and using it for the fuel pump stuff. Maybe that's the way I should go. It's hard to believe no one has mounted a fuel cell under the car though (without cutting through the trunk, I've seen those threads).

I considered the external pump idea, using an Aeromotive A1000 pump. Would only need 1 of those, but I didn't know about the sump issue..that would have to be added to a stock tank of course.

Thanks for the response, not getting much love on this thread lol
 
There is a huge difference between a real fuel cell and just another metal or plastic box that holds fuel. A real cell is made to be crashed and not spill fuel everywhere and burn you to death, also commonly a few thousand bucks. What everybody uses in a typical drag car it just a different shaped box, normally with a built in fuel sump to feed an external sump. Unless the stock tank will not work for whatever reason, replacing it with a drag type "cell" doesn't really do anything but create more work. I personally hate aeromotive stuff but again might just be my luck with it. I know you want to run it on regular gas, whats your hp goal? If sub 700 a single walbro will drop right in the stock volvo tank hole and be the most logical solution. I guess they make one that flows even more now, http://walbrofuelpumps.com/walbro-f90000285-fuel-pump-525lph-e85-compatible-tiautomotive-tcd470.html
 
walbro 450 in the tank and upgraded lines. works well with the 80lb injectors at 3bar.
 
I've seen those charts with fuel pumps, this is a weird comparison but back when I used to build big car audio systems, it was the same problem with voltage. Running amplifiers at very low ohms really needs full voltage, 14.5 VDC if possible. I have an old school Orion dual battery voltage regulator which ensures 14.5 V output, I will probably use a similar, more modern unit, or a big capacitor.

55superbeetle, your choice was closest to my 3rd option, cutting a hole in the stock tank and using it for the fuel pump stuff. Maybe that's the way I should go. It's hard to believe no one has mounted a fuel cell under the car though (without cutting through the trunk, I've seen those threads).

I considered the external pump idea, using an Aeromotive A1000 pump. Would only need 1 of those, but I didn't know about the sump issue..that would have to be added to a stock tank of course.

Thanks for the response, not getting much love on this thread lol

an A1000 is a pile of junk noisy ass fuel heater which needs a sumped tank to work properly.

If you want to do an overkill setup without cutting a bunch of holes in your car or changing the world to make it happen, just use a surge tank in the trunk with a pair of walbro 450s in it and a 255 in the tank feeding it.


Like this:
howdoesafstworkinternalfuelpumps.jpg



I am probably going to use one of these surge tanks on my own car (500-600whp T6 swap):
http://www.radiumauto.com/MPFST-Multi-Pump-Fuel-Surge-Tank-P271.aspx

good quality and locally made to me

I MIGHT also go ahead and take the plunge on one of their cells, though:

http://www.radiumauto.com/Fuel-Cell-with-FCST-P893.aspx

Just a bit hard to swallow $2500 including pumps
 
I like that setup, its a lot of parts but kinda what I'm looking for. The surge tank looks cool also haha.

Linuxman, the sending unit ports are big enough for that?
 
the return is. I think for the feed I just drilled out the old feed and put a -6 an bulkhead fitting in there.
 
yeah I don't have any pictures of that, it wasn't really that big of a deal.. oohh wait. I did not drill out the old fuel feed. I used it as a port to run heavier gauge wiring in for the 450, and just put a bulkhead connector on there somewhere. The car did probably made 500whp on the stock 940 turbo fuel pumps, with a adapter to go from the oem fuel filter to the aftermarket rails I've got. fyi the oem fuel filters do quite well.
 
I did something sort of similar with my 740
128613115.jpg


except it feeds a surge tank that then fed two bosch 044's
 
Have you had good experiences with Walbro pumps? People seem polarized on them, my hill climb buddies and German car guys hate them, others seem to love them. I'm considering the surge tank in Revolvrs link, but they only fit Walbro or AEM pumps, the 044 is to large of a diameter.
 
Have you had good experiences with Walbro pumps? People seem polarized on them, my hill climb buddies and German car guys hate them, others seem to love them. I'm considering the surge tank in Revolvrs link, but they only fit Walbro or AEM pumps, the 044 is to large of a diameter.

I haven't had any issues, but you gotta be careful when buying. I think a lot of the issues stem from people getting knockoffs.
 
Back
Top