LS7 fuel system

[RussF]

V8 Vum said:

RussF said:

SM-Engineering (based in UK) did a great job with mine--> http://www.sm-engineering.co.uk/

3x -6 inlets, 1x -10 outlet and a -8 return. 250mmx100mm

Edited by RussF on Friday 12th December 12:36

Russ
Was your for an LS7 config? If so have you got any diag or pics as to how you connected it up to the fuel lines?

Oh, and where did you mount it?

cheers

keith

Edited by V8 Vum on Friday 12th December 13:50

Hi Keith - Yes for a LS7 but not fitted yet. It will be along the lines of this ....

Tanks will have -12 crossover similar to crafty. Surge tank fed from two low pressure pumps and the return from the fuel rails. -10 outlet from surge tank feeds high pressure pump via a 100 micron filter which in turn feeds the two rails via a 10 micron filter and a Y block. Then through the regulator and back to the surge tank. -8 outlet from surge tank back to tanks. Looking to implement some valves to reduce overfilling tanks etc. High pressure pump will be speed controlled to assist with recirculation.

[Steve_D]

V8 Vum said:

Hi Steve,
Will yours be for an LS7?
Any reason not to go Flat?
Are you using the same screw-type outlet and inlet flanges as RussF?
keith

Mine will be for my SBC 407. Am fitting a Holley Stealth Ram injection manifold and a Megasquirt ECU I am currently building.

If the return pipes are correctly positioned tangential to the side of a round pot then the returning (potentiality aerated) fuel will spiral round the inside wall of the pot allowing time for the air to rise and leave the pot via the top fitting and back to the fuel tank. This is important in a dry sump oil system but I don't believe is so relevant in fuel. On that basis I am happy with a flat tank which will fit neatly against the bulkhead.

The tank they are going to make for me will have the same screw fittings as the round one shown in Russ's post. Also note that the fittings on that pot are not tangential so will not produce a 'Swirl'.

Steve

[RussF]

Steve_D said:

.....Also note that the fittings on that pot are not tangential so will not produce a 'Swirl'.

Steve

This was intentional Steve as I agree with your assertion that a "swirl" is not required in the fuel system, simply a head of "stable" fuel. Would have been happy with a "square" one but was struggling for space to mount it! A cylindrical one suited my needs better.

[CanAm Dave]

Hey Russ

Your CAD drawing looks very similar to my own setup that I did a couple of years ago. I used an off the shelf ATL swirl pot from Demon Tweeks. The bottom outlet was changed to -10 though.

Regards Dave

[V8 Vum]

Steve,

Err....can I ask that you order two?
pretty please!

cheers

keith

[Steve_D]

V8 Vum said:

Steve,

Err....can I ask that you order two?
pretty please!

cheers

keith

Will scan the sketch and send it to you and SM on Monday.
Will then call them and see if I get a better price for 2.
PM me so I have your email address.

Steve

[738 driver]

Dave, that looks to be a good installation all round,the location...nice and low away from warm-air build up and are those rubber mounts we can see too! Very very nice...... a good example to follow IMO.

[CanAm Dave]

738 driver said:

Dave, that looks to be a good installation all round,the location...nice and low away from warm-air build up and are those rubber mounts we can see too! Very very nice...... a good example to follow IMO.

Cheers Dave

Yes the pumps are on anti-vib mounts. The only thing I have changed since then are the low pressure pumps. The ones I originally used were Aeromotive street pumps, they were of the sliding vane type and just too loud. I could hear them over the engine. I changed them to Holley HP125 Gerotor Type which are much queiter in operation. The system works very well in practice. I've done a few thousand miles now and have no issues with the system.

Regards Dave

[wherzmespana]

Just as a 'heads up' - I note that on the Cad layout the regulator returned to tank? I had problems with aerated fuel in the swirl pot(1.5 litre pot) - running full throttle and then lifting off for a corner and then back on the gas - for the sake of another pipe to the tank return I would return to tank to be safe. Again, this took a while of frustration on track to sort. Some of the installs in the photos look fantastic - if only mine looked so good - mine falls into the 'functional' category!

[RussF]

wherzmespana said:

Just as a 'heads up' - I note that on the Cad layout the regulator returned to tank? I had problems with aerated fuel in the swirl pot(1.5 litre pot) - running full throttle and then lifting off for a corner and then back on the gas - for the sake of another pipe to the tank return I would return to tank to be safe. Again, this took a while of frustration on track to sort. Some of the installs in the photos look fantastic - if only mine looked so good - mine falls into the 'functional' category!

Thanks for that info, interesting. Can I ask, did you return to the top or bottom of the main tank?

Edited by RussF on Thursday 18th December 21:27

[wherzmespana]

To the top - I used a tee connection to join the return from the swirl to the return from the regulator immediately before the tank inlet. My previous note probably relates to more track orientated cars - where fuel demand from the swirl is either 100% or nothing but still worth thinking about it if you are going to blat it around a track as my LS1 would stutter with the high pressure fuel system fluctuating wildly between 75 psi and nothing.

[spatz]

sounds like that the pollak valves are nor very reliable, neither could a find a spec for the internal bore.
after some googleing i found a 3/2 valve with internal bore of 13mm that gets very good reviews of the biodiesel community



http://www.poelmax.de/product_info.php?products_id...

they are 60 euro each and you would need 2 of them for a LS7 system.

Edited by spatz on Saturday 7th February 14:09

[spatz]

One more question on the fuel system for LS7, the french use the LS7 setup usually with a dual Bosch 044 pump kit.
I bought one of these pumps thinking at 200 liter/hours it would be enough ?
The french engineer mentioned that lack of fuel increases your exhaust temperature and is decreasing the general performance of the car ?
They actually do not use the prefueling pump but only use the BOSCH pumps with a direct feed from the tank but probably with a single tank only.

As I intend to install a FACET pump (bought one already) for prefueling the swirl pot, I probably would also need a dual pump kit for the facet ( which is available) , otherwise the FACET pump would actually limit the flow if the swirlpot is empty.
I do not really want to install 4 fuel pumps in the car ,mainly because of the noise and the big thirst of the Bosch (14amps.
Maybe I should wire the car up with the one Facet and one Bosch and wait for the results ?
What is your opinions ?

[Steve_D]

spatz said:

One more question on the fuel system for LS7, the french use the LS7 setup usually with a dual Bosch 044 pump kit.
I bought one of these pumps thinking at 200 liter/hours it would be enough ?
The french engineer mentioned that lack of fuel increases your exhaust temperature and is decreasing the general performance of the car ?
They actually do not use the prefueling pump but only use the BOSCH pumps with a direct feed from the tank but probably with a single tank only.

As I intend to install a FACET pump (bought one already) for prefueling the swirl pot, I probably would also need a dual pump kit for the facet ( which is available) , otherwise the FACET pump would actually limit the flow if the swirlpot is empty.
I do not really want to install 4 fuel pumps in the car ,mainly because of the noise and the big thirst of the Bosch (14amps.
Maybe I should wire the car up with the one Facet and one Bosch and wait for the results ?
What is your opinions ?

Why would you want two?
One of those pumps can empty both your fuel tanks in 16 minutes.

I have seen somewhere an online calculator that will tell you the flow rate required to support the power of your engine. Will have a look and see if I can find it.

Steve

[Steve_D]

Right found one.
Bosch 044 pump produces a minimum 5 litre/min.

700HP requires 4.368 litre/min.

So will you be running more than 700 ponies?

Steve

[spatz]

no that was my initial thought and these racing guys made me confused. I always thought this pump is plenty enough !
The swirl pot that I will use will work as a short time reservoir so that the Facet pump must not really pump the same volume.

thanks Steve

[Steve_D]

spatz said:

......The swirl pot that I will use will work as a short time reservoir so that the Facet pump must not really pump the same volume.....

Sorry have to disagree with you.
If you are using 700hp then you will empty the pot in about 30 seconds.

Steve

[spatz]

Sure but only under the condition that the facet pump is not pumping and it actually also does 170 liters/hour.......so almost as much as the Bosch does. And I will use a standard LS7 that is specified 505 hp, so I hope you can agree now

[Steve_D]

spatz said:

Sure but only under the condition that the facet pump is not pumping and it actually also does 170 liters/hour.......so almost as much as the Bosch does. And I will use a standard LS7 that is specified 505 hp, so I hope you can agree now

Yes, at 505HP you will be OK.
The spec sheet I was looking at had the Bosch pump producing 300 litres/hour so would be quite a mismatch to the Facet.

Steve

[Ramthorne]

I run my standard LS7, not in an Ultima, with a single Bosch 044 and have had no problems. I do have twin pumps in the tank but only run them singularly.

I have a single fuel tank to which I fitted an ATL collector, this also holds the pumps. I put the regulator (again from ATL) and filter in the tank so I had a single pipe running from the tank to the engine.

I assume having two tanks complicates things, I was keen to have it as simple as possible