Fuel tank mod

[etxxz]

i was even considering a single transfer pump. so what if it runs dry every now and then? it may be good enough unless you're too low on fuel and on a tight track like CMP per say. dual would be optimal short of a fuel cell.

The surge tank can be small enough, to fit where the fuel filter is and relocating the fuel filter if it doesnt fit there as well. It can by cylindrical (to avoid having to fabricate a box), top threaded hat with oring, bulkhead fittings... i'm sure if i put my head to it i can make something that'll work awesome in that space. Doesnt have to be greater than 1gal either. I was thinking 1qt 2qts max fuel capacity. The rest of the space is occupied by the internal pump and the surge tank itself. It could also be an external pump feeding vertically (directly or indirectly) on an "empty" surge. I'm just throwing ideas right now out of the top of head. You have more track exp than me, i haven't considered in full all the safety aspects.

[jlevie]

^^ yup

i'm in the making of an accumulator type tank with my current high pressure intank pump inside. I will replace the intank pump with a low(er) pressure, high volume pump such to keep the accumulator tank always filled and the high pressure pump always submerged completely (cools it too). This is probably the closest thing to actually having a fuel cell. I think this is the best solution our cars will see.

I can still see starving with that setup. definetly less, but its 'not a wow that's the ticket!!' kind of thing.

I agree that dual transfer pumps feeding a small surge tank that then feeds a high pressure pump would be the ideal solution. And I considered doing that. But in my opinion that would require that the surge tank be a small 1-2 gallon fuel cell or it would require fabricating up a sealed rear bulkhead. There's just no where else inside the "safe area" to mount a surge tank. By safe area I'm referring to the part of the car that is inside the cage mount points.

The other solution is of course a fuel cell. But they are pricey, you have to mount it outside of the cage envelope, and it will increase the polar moment. After my wreck I won't put anything that can create a safety hazard outside of the cage envelope.

[jlevie]

I would not have put that much work into the mod just for track sessions or sprint races. For those I want the tank full each time for weight balance and it is no big deal to top up the tank before each session or race. But in enduros that don't required timed refueling stops I want to run the tank down as far as possible to reduce the number of refueling stops and the amount of gas I have to put in.

[etxxz]

^^ yup

i'm in the making of an accumulator type tank with my current high pressure intank pump inside. I will replace the intank pump with a low(er) pressure, high volume pump such to keep the accumulator tank always filled and the high pressure pump always submerged completely (cools it too). This is probably the closest thing to actually having a fuel cell. I think this is the best solution our cars will see.

I can still see starving with that setup. definetly less, but its 'not a wow that's the ticket!!' kind of thing.

[CincinnatiKid]

That's a nice little mod, I hate being at the track, a bit low on gas, come fast around a corner and mid corner the power just dies, straighten out, and it's back to life.

[mazur]

That's not just plain old copper tubing, right?

[jlevie]

Now that is nice little hack. Not too expensive and works perfect

In my case the only parts cost were the copper fittings. I salvaged the pump and level sensor out of my previous (wrecked) Spec E30. But even if I didn't already have the pump and sensor I'd have done it anyway.

[george graves]

Now that is nice little hack. Not too expensive and works perfect. Good work sir.

[Bishop]

Very cool Jim

[gearheadE30]

can't say I've ever seen anyone with a good setup to work around this issue...in fact, I didn't even know it was much of an issue until I lost power getting on the highway with less than an eighth of a tank once haha

[jlevie]

To help prevent starvation when the tank is low I added a transfer pump to the left side (where the level sensor used to live). The fuel is routed into the high pressure pump pickup bowl. The transfer pump is one from a dual pump set up.