What To Do?

[mic]

shud be sweet.

[The_Bogan]

if your chasing 400rwkw I would just go with a process west surge tank kit, depending on what injectors you use you will gonna be getting piss poor fuel economy if you drive you car everyday, and also depending on what injectors you are using you are going to be using ash*tload of fuel on startup.

for anything under 400rwkw I wouldnt even bother with a surge tank, I would stay with an intank pump and just not give it a bootfull with anything less than 1/4 tank of fuel.

Edited 23/02/09 11:19 AM by The_Bogan

[01txr]

  typhoon_freak said:

very interesting read there and a lot to take into consideration.. so you wud put the fuel filter after the surge? also.. if I was to swap the pumps over to a bigger one, you wudnt need a retune wud you? like wudnt push more fuel in?

May have not explained myself properly about filters after surge tank.

Best to run your filter after the surge tank pump.

By doing it this way the it makes the intank pump able to supply a little bit more fuel volume to surge tank

by not having the restriction of the filter in place making for a smaller surge tank requirement.

If you calculate everything out like Fuel flow per hour WOT that engine requires at x hp/kw and you know

what your pump/s are rated to flow you can work out what size surge tank is required. Convert back to Flow per Seconds so you can work out how long x liter surge tank can supply required fuel.

Keep in mind if the intank pump is poor the surge tank will need to be larger.

For circuit work the surge tank needs to be larger for the time duration of the WOT applications.

Eg say your engine draws 60lph (17 mls per sec) and your surge pump flows 80lph and intank only flows 30lph (13 mls per sec).

Ignore the surge pump as we know it will supply the fuel, the problem will be the intank pump and the size of the

surge tank to how long WOT is used.

Now say surge tank is 1 litre, the engine would empty the litre tank in approx 60 seconds with no intank supply.

Add intank pump replenishment of half the flow as above and you would be looking at the surge tank running dry within 30 seconds more.

This would be alright as long as WOT is only held for a safe period of 60 seconds all depending surge tank design on scavaging low level fuel.

And pending how soon after that full throttle is applied and held for.

If you run both intank and surge pumps of same flow rates in excess of engine requirement you will have lots of fuel recirculation

when driving at low throttle percentages unless you use pressure switches on both pumps to cut the flow down when not required.

The best systems are always very complex in design, just look at any hi profile circuit racecar.

All comes down to how long you will be holding WOT.

Basic Step by step of a basic setup

Intank pump picks up fuel and pushes it to the surge tank

Exit from surge tank to 2nd pump (Surge Pump)

2nd pump then pumps to fuel rail

fuel pressure reg (FPR) holds set pressure to injectors

FPR releases unused fuel to fuel tank.

No retune needs to be performed unless you are running higher or lower fuel pressure

from the pumps and your FPR cant bleed off enough fuel.

You will need to upgrade the FPR from the factory one as the factory FPR was never designed to support the power level

you are aiming at or the Fuel Flow rate.

In the case your you end up running higher fuel pressure the injectors will flow more fuel to engine giving a rich mixture resulting in black not blue smoke.

You might find if the fuel pressure is not excessively higher the ecu will compensate and adjust injectors to suit fuel mixture anyway.

Hope I have been helpful, and if I am incorrect in anyway with my knowledge please let me know.

Also better say I am not responsible or liable for any damage or harm for my suggestions.

And if doing any fuel system work consult with a expert.

Fuel systems are very dangerous, never cut corners and always put plenty of though into it.

I also try to use least amount of flexibble hose as possible as it is more prone to blow then pipes and quality fittings.

not to mention hose always eventually perishes.

near had my a car of mine burn to the ground due to fuel filter that should of never been put on a self without a pressure

warning on it.

It broke on a carb'd 351 running holley blue and reg set at 7 psi.

dumped a gut full off fuel all over the engine.

I had my 2 yo daughter in car at time, tried ripping her out of baby seat without undoing seat belt.

evenually carmed self and undid it.

then attended to car.

the whole engine bay was burnt, lots had to be replaced, car stunk for months after.

Very scary.

Woke the whole neighbourhood 6am sunday morning with a large boom.

So be very careful if intending on doing fuel mods especially on high fuel pressured cars like ours.

Fire Extinisher is a great mate.....

Prevention with a well designed setup is even better.

[typhoon_freak]

  The_Bogan said:

if your chasing 400rwkw I would just go with a process west surge tank kit, depending on what injectors you use you will gonna be getting piss poor fuel economy if you drive you car everyday, and also depending on what injectors you are using you are going to be using ash*tload of fuel on startup.

for anything under 400rwkw I wouldnt even bother with a surge tank, I would stay with an intank pump and just not give it a bootfull with anything less than 1/4 tank of fuel.

I didnt really wanna go buy a surgie, more fun making one, and there not that hard to make.. plus its like 1 tenth of the cost to make one.

[Paul@eliteauto]

My cars dont run surge tanks.

My T running 375 rwkw is st just running a in tank pump.

My BF Typhoon same story.

Bosch 044 pumps are good but bloody noise no mater how I hhave seen them mounted.

2 in line fuel pumps can cause issues on start up running rich causing black smoke till you give it a jab on the throttle.

Keep the things over quater of a tank when your giving hell and you wont have a problem.

Whey spend money when you dont have a problem.

that's my 2 cents.

Cheers Paul