Fuel surge tank

[stevenr816]

I've been looking up different setups on cars. My cars going to be mainly a drag car but also going to have street use and some road race/auto x/ and drift stuff.

My question is how can you have an intank 255 lifter pump supplying a huge a1000? Is it cause the lifter pump isn't under pressure so the 255 gets bumped up alot? Cause 3 liters isn't that much gas to save up

Here's one pic

And the setup on paper

 

[stevenr816]

Plus I think it will technically and a couple gallons depending on how big I build it. May need it depending on how amazing a 800hp 7m's fuel economy is on the street

 

[MDCmotorsports]

The A1000 is there just to feed the engine. The Walbro is there JUST to keep that little tank full. 10lbs of sh!t through a straw for a tube my man.....

 

[stevenr816]

Right. But on paper it doesn't add up. A 255 supplying a 1000. If the 1000 was at max flow I don't see how the 255 would keep up with it after the tank was empty. Also i don't get your reference

 

[northwestsupra]

I agree it doesn't add up. But I also don't understand the point of the surge tank.... is this like a alternative to a sump? Maybe the smaller walbro is just a pick up? Someone who understands this better will shoot a better answer than me.

sent from my ultimate droid

 

[mkiiichip]

The small pump is making no pressure, its just moving fuel.
The large pump makes high pressure on a large area. What makes pressure? A restriction to flow.
Therefore the small pump can "out flow" the large one, because of the different jobs they have.

Also the return from the high pressure system goes to the surge tank. So the small pump only has to supply as much fuel as the injectors are supplying to the engine, at any given time.

 

[mattsplat72]

^ thanks

 

[Enraged]

i was wondering about this as well, as it seems like a good alternative to sumping the stock tank.

 

[northwestsupra]

i was wondering about this as well, as it seems like a good alternative to sumping the stock tank.

I sumped mine. But I was still curious
sent from my ultimate droid

 

[northwestsupra]

If I'm looking at the diagram correctly the tank holds your fuel. The low pressure pump fills the surge tank. The high pressure pump takes the fuel from the surge tank to the injectors. All returned fuel returns to the surge tank. If the surge tank over-fills with fuel it returns to the tank. So it makes sense to use a small pump just for the surge tank

Also the a1000 is required to be at the same level or below the tank. I think the walbro can be placed anywhere. But I may be wrong
sent from my ultimate droid

 

[IJ.]

If the return is going straight to the Surge tank you're going to heatsoak it's fuel much sooner due to the small relative volume.

Larger the pressure pump the greater the volume of returned fuel unless you have some way to PWM the pump and slow it down off boost, the more returned fuel the sooner heat soak sets in and you need some way to compensate for the temp rise, modern cars run a sensor in the line/rail.

 

[northwestsupra]

And the pwn through aeromotive is almost 200 if I remember. Good info though ij

sent from my ultimate droid

 

[stevenr816]

So should I just stick to a dual or triple pump then lol or make a fuel cell

 

[IJ.]

My last setup was dual Denso uprated mk4 style pumps and I had them controlled by the ecu with each having it's own off/on/speed all based on demand/boost, I ran them in the 115L tank in a baffled area with fuel tanks foam surrounding them, 0 surge issues and it made heatsoak a non issue.

 

[aye mate]

Did that setup have a return, IJ?

 

[IJ.]

Did that setup have a return, IJ?

It did but the flow back was minimal due to be able to change the pump speeds/volumes, running the pumps uncontrolled would heatsoak the entire tankfull in about an hour and a half of freeway driving to the point the tank was hot to touch and this threw the fuel mapping out at idle and around town in stop start driving.

While none of this is essential I'm just pointing out that it's an issue and I like my fast cars to drive like stock with no bad habits if possible.

 

[northwestsupra]

So how about my setup then. Stock tank. Sumped. Aeromotive a1000. 880cc inj. High flow rail. Aeromotive fpr. Back to tank. Dual -8 feed. 6 return.

Heaksoak at all?

sent from my ultimate droid

 

[stevenr816]

How are you guys baffling the stock tank?

My setup would be stock tank, dual or triple mk3 255 pumps with individual powers, 1250s, afpr, online filter, dual stock lines feeding the left and right side of the stock 7m rail with the cold start line being the return.

The individual pump powers would also switch fuel maps from street to race gas tune. So the pump being on would be set to minimal

 

[IJ.]

So how about my setup then. Stock tank. Sumped. Aeromotive a1000. 880cc inj. High flow rail. Aeromotive fpr. Back to tank. Dual -8 feed. 6 return.

Heaksoak at all?

sent from my ultimate droid

At cruise/idle the injector pulsewidth is tiny with large injectors if you're not slowing the pump under these conditions you're returning a huge volume of fuel to the tank and constantly recirculating it through the Hot engine bay and Rail means it has to heatsoak Trevor.

How are you guys baffling the stock tank?

My setup would be stock tank, dual or triple mk3 255 pumps with individual powers, 1250s, afpr, online filter, dual stock lines feeding the left and right side of the stock 7m rail with the cold start line being the return.

The individual pump powers would also switch fuel maps from street to race gas tune. So the pump being on would be set to minimal

If I were to use a stock tank I'd drop it and squeeze a bunch of foam blocks inside, the stock tank has a plastic labyrinth chamber around the pump pickup and is pretty well designed but the rest of the tank is fairly open so you get a lot of slosh, the foam minimises this.

 

[aye mate]

Never heard of that, IJ. Is there special foam just for fuel tanks? I would think that regular foam would break down and suck fhit up.