Fuel pump & tank

[AlexFocusST]

As the title suggests ,

What fuel pump(s) , swirl pots and fuel tank does everyone use to compensate forfuel starvation in corners .

Personally with the oem setup , car would fuel starve even with half a tank of fuel...

Opinions , suggestions and photos welcome

BR
Alex

[scottie_436]

Use oe pump to fill swirl pot, 1l or maybe 2l is big enough. Then theres plenty of oe inline pumps available on ebay ,motor factors ect. Theres no real need to go with fancy pumps. Just choose one from a car that has the same power sort of power that your runnng.

:)

[MuZiZZle]

Use oe pump to fill swirl pot, 1l or maybe 2l is big enough. Then theres plenty of oe inline pumps available on ebay ,motor factors ect. Theres no real need to go with fancy pumps. Just choose one from a car that has the same power sort of power that your runnng.

:)

fo sheezy?

so all the jazzy setups are overkill?

[scottie_436]

If your running big power then sure... Its worth the expense

The standard intank pump is capable of at least 180 -190 bhp. Its fuel starvation during cornering that saxo suffers from badly. So a swirl pot fed from the standard tank using the standard pump is fine.

Then as said previously theres a good choice of non branded inline pumps available to feed the engine from the swirl pot

Certainly no need to waste money on branded kit..... Unless your a bling king that is ;)

[MuZiZZle]

So I stick a swirl pot after the existing pump

Then a pump after it, leaving the return back to the original tank?

[scottie_436]

Exsisting pump feed to swirl pot
Vent from swirl pot to tank
Feed from swirlpot via inline pump to engine
Return from engine back in swirl pot

[MuZiZZle]

Where's best for these bits then ?

[DanGT]

I run my car at 900kgs due to regs, with a 3/4 tank of fuel and semi slicks and I dont get fuel surge! Make sure your pick up is pointing the right way, the saxo fuel pump has an in built swirl pot so should be ok unless running alot of power.

[AndySAXO]

I run my car at 900kgs due to regs, with a 3/4 tank of fuel and semi slicks and I dont get fuel surge! Make sure your pick up is pointing the right way, the saxo fuel pump has an in built swirl pot so should be ok unless running alot of power.

i still use the standard system on the track now for a few years, even with 1/4 tank i havnt had any fuel problems. i am changing to a different system, but that for different reason, but not had a problem yet.

[sexy_gt]

never had a problem with fuel either!

only fitting swirl pot now due to supercharger

[106maxi]

Never had a problem either.

[jpsaxo]

I only had issues if I've got less than 1/4 going round gerrards (@mallory) which is the longest right hander in the country

I'm running the standard set up on my new engine so we will see how that fairs...

[axsaxoman]

running tak low and high cornering or acceleration loads (1g+) then it is a problem on the saxo .
once you get below 1/3 to under 1/2 its a big problem .

if you haven,t had the problem --you ain,t going quick enough

[DanGT]

if you haven,t had the problem --you ain,t going quick enough

LOL! How are you measuring your cornering loads of +1g?

From experience of racing on many circuits in this country, the only places Ive had surge (running much less than a quarter of a tank) is at the bottom of craner curves at donny and coming out of luffield and round woodcote at silverstone. Doesnt really happen unless your running slicks or really low fuel. No point in spending £££ if you dont need to.

[sexy_gt]

^^ i would of guessed at data log.

[axsaxoman]

no I am not measuring it --no need
if fuel is not in bottom of tank ,then the g force must be enough to make it move to one end of tank --yes its probaly not 1g on most cars
suspend a small wieght from the interior mirror and see how far it goes sideways in a long corner if you want to see what your fuel is doing in the tnak --but enough to cause a problem

[solvi]

LOL! How are you measuring your cornering loads of +1g?

From experience of racing on many circuits in this country, the only places Ive had surge (running much less than a quarter of a tank) is at the bottom of craner curves at donny and coming out of luffield and round woodcote at silverstone. Doesnt really happen unless your running slicks or really low fuel. No point in spending £££ if you dont need to.

mesured or not...

its a real problem in a saxo , notisted many times at estoril PARABOLIC,
and starts at 1/2 fuel capacity..


its a FACT..

[Dave_P]

An old pic but you can see my swirl pot. My 2nd pump is an Astra gsi in line pump.

http://i334.photobucket.com/albums/m433/16v_rallye/IMG_2457.jpg

I didn't used to suffer fuel starvation issues with my 166bhp engine (708 catcams & TB's) it only started when i fitted the new more powerful engine.

[Ross]

http://i881.photobucket.com/albums/ac16/Lee_GtiDiablo/1ab73177.jpg

But now removed as I drive like a pussy and want back seats.

[Dave_P]

Potentially lethal! ^ :fcuk:

[Ross]

Point out the faults Dave? We didnt know better.

[Dave_P]

Point out the faults Dave? We didnt know better.

Everything you see shouldn't be in the passenger compartment.

[Ross]

Figures!

We didnt know how to do it so copied a professional Motorsport preparation companies installs.

[Dave_P]

We didnt know how to do it so copied a professional Motorsport preparation companies installs.

Really?!

You wouldn't be able to compete in a car with its fuel system on display like that.

[wadoryu]

Big metal pot of fuel inside passenger compartment, better you than me Ross *scared*

[Ross]

Really?!

You wouldn't be able to compete in a car with its fuel system on display like that.

Yep really...

I should point out both "professional" and "Motorsport preparation" are their terms not mine... My views on the company are well known.

It's how their own, and their customers cars, are outfitted.

http://i639.photobucket.com/albums/uu114/106-gti-colin/Image001-1.jpg

http://i128.photobucket.com/albums/p179/saxmad88/21052009651.jpg

Appreciate why now - a roll with that setup could be a disaster. :(

I'll certainly not run it like this again.

There's lots of people running it like this, so I guess we all need a reminder of safety...

http://i737.photobucket.com/albums/xx14/chris1cherry87/106%20turbo/DSC00452.jpg

[jpsaxo]

This is EXACTLY why I don't have a swirl pot ^

We were having fuel starvation at around 7,000rpm on my SB engine with the standard pump, but more alarmingly we were getting fuel starvation on hard acceleration as well.

To combat that we fitted a 225 walboro Intank fuel pump inside the standard tank, it was a bit of a pain and very fiddly, but it cured the problem and is good for over 300bhp using the standard fuel lines apparently

[Ross]

I've done a 255 into the stock swirl pot twice now on two cars, it's a pain in the arse tbh! But I was using a 255 intank to ally swirl pot, then a 255 external to fuel lines. Now I'm just running the 255 in tank so we'll see if it leans out, but I doubt it. The calculations on paper look good.

[axsaxoman]

dave-- you are right
also its plumbed in wrong --return to the tank should be the top connection ,so any air goes back to tank+ tank is kept full of fuel
to keep to the EXACT wording of the regs you should have no fuel container with the passenger compartment .
yes fit it in the back ,but then you must build a sealed box around it all

[jpsaxo]

It should be fine i reckon mate, they say fine up to 300bhp but id imagine 350 it should be fine. what are you going to be running?

[Ross]

thanks John we did actually fix that after the photo was taken - that explained a symptom we had of starvation where the external pump couldn't actually pump and would seize. Was drawing against a vacuum. Sorted when we swapped the lines round. :)

I'll not be running one again I dont think, and if I did, would relocate the setup elsewhere.

Thanks for the input on my old setup guys - really appreciated.

[Ross]

It should be fine i reckon mate, they say fine up to 300bhp but id imagine 350 it should be fine. what are you going to be running?

Power wise? Around a (genuine...) 350.

John, what would you suggest if we run into issues with the walbro 255 flow wise? Do I have any more intank options?

[axsaxoman]

I never had change std pump because of lack of volume --std pump can move 40 gallons an hour @3bar --so unless you have fitted an 8litre v8 I can,t see why you would need a bigger flowing pump
even with 490cc injectors thats only 0.43galons a minute ,if they were running 100% and at max of 80% thats 0.3gallons a minute ,and that would be good for 400+bhp
starvation caused by tank level has nothing to do with pump volume

[Ross]

I never had change std pump because of lack of volume --std pump can move 40 gallons an hour @3bar --so unless you have fitted an 8litre v8 I can,t see why you would need a bigger flowing pump
even with 490cc injectors thats only 0.43galons a minute ,if they were running 100% and at max of 80% thats 0.3gallons a minute ,and that would be good for 400+bhp
starvation caused by tank level has nothing to do with pump volume

That's interesting.

Josh (above) had back to back dyno sessions with standard then 255 pump. When being mapped by Sandy, the standard pump could not supply enough for his configuration, which is around half of mine (power wise). He swapped to a 255, and it was fixed. No other changes.

I run 4bar with 630cc injectors. I hope the 255 can cope. Confused though!

[axsaxoman]

thats easy --std pump was fucked or it was 1.4 pump ,which is smaller output than a 1.6 pump,or he was running very high pressure --raise pressure too much and the volume drops dramtically

[tweeqd]

ross the Aeromotive 340 fits in the standard tank dead easy and is the same size as a standard pump, they have been tested up to 700bhp on evos so should be ok for a saxo

i have one in mine to cope with the nitrous but even with the standard intank swirl pot you will get starvation on track under 1/4 tank

[Ross]

ross the Aeromotive 340 fits in the standard tank dead easy and is the same size as a standard pump, they have been tested up to 700bhp on evos so should be ok for a saxo

i have one in mine to cope with the nitrous but even with the standard intank swirl pot you will get starvation on track under 1/4 tank

Thanks martin, really appreciated :) I'll see what happens when mapping comes around but I'll remember this for sure :)

[tweeqd]

a Bosch 023 as run in the audi RS's is not much bigger than a walbro and will fit with some work
they have been used on 500bhp+ cossies without an issue

i was going to run an 023 in mine but lots of good reviews on the aeromotive on the MLR and imported from the USA there only £110

[jpsaxo]

thats easy --std pump was fucked or it was 1.4 pump ,which is smaller output than a 1.6 pump,or he was running very high pressure --raise pressure too much and the volume drops dramtically

It was the standard 1.6 vts pump John. We are using a 3bar fpr. Most alarmingly was that it couldn't supply enough fuel on hard acelleration either

[axsaxoman]

It was the standard 1.6 vts pump John. We are using a 3bar fpr. Most alarmingly was that it couldn't supply enough fuel on hard acelleration either
then your choices are bad pump--most probable ,partially blocked filter .fuel lines or some sort of rstrictor in plumbing -were you using std fuel reg--alot of the remote fuel regs have very small internal pipe sizing -which will reduce flow rate -did you actually check fuel pressure to see if it was dropping under load?
I only run std in-tank pump on my car with a front mounted swirl pot + in line pump and never had any problems --even when i only used std pump i only had problems when level in tank was too low
the std pump is same as used on the xantia 3.oltre v6 and thats over 200bhp in std form .
technically the lines from back to front of car are a little small -only 6mm internal --which is why if changing lines I go for 8 or 10mm copper lines front to back .
small fuel lines can cause a transient problem on accel if system is border line on capacity
If you asked a pump maker they would suggest 12mm feed lines from pump at back to reg at front . for this reason , to give a reservoir of fuel at high pressure to smooth out transient pressure /volume demands
but using an return pipe of a smaller diameter
are you using std saxo wiring loom ?

[Sandy309]

The problem was that I couldn't provide enough transient enrichment at all speeds or base injector duration beyond 7k. I did suspect the lines and the condition of the pump, or it's basic delivery, which was unknown to me. All the previous cars I've had running engines like Josh's have been competition cars with custom tanks and lines, but still single pump in tank and I always use Bosch or Weber fixed regs in our own or Weber housings, by the rail. The ECU wiring was all my brand new competition spec, a substantially proven set up! Time was running out on that mapping session and I knew there was a fuel delivery issue at high demand; Josh had to leave, so I advised him of the problem and the likely solutions.
Obviously changing the pump to the uprated one was the easiest/cheapest fix to try and my suspicions were clearly correct, because it worked. The whole map needed to be revised. Ultimately he'll still need to run it over half a tank to resist surge and a custom tank would be the best solution to me, I'm not keen on engine bay swirl pots.
Whether or not this particular pump was weak, it's a common problem from what I've seen and leads me to heartily recommend replacing the standard pump when fitting a new higher spec engine, because the old pump is likely to be tired by now regardless.

Footnote; this year I've been working with a friend developing class one Lamborghini powerboat engines, they're reputed to be in the region of 960bhp already and the factory engine has a single -6 JIC fuel line. Surprised me.

[axsaxoman]

I can see why sandy suggested what he did.

you have to remember that if a pump sucks air then it is running dry on the vanes =that can destroy them in a very short time period ,so it would not suprise me to hear the std pump had lost capacity + pressure if it sees surge +starvation
this is whyreal race fuel systems costs lots of money and look very complicated
no pump likes sucking dry