ls1 fuel pump 500+bhp
Discussion
cross posted from the hsv holden forum....
i have fitted a CF supercharger to a 5.7 ls1 and think that the fuel pump is now the weak link? 340bhp now up to 530bhp
what type of pump is recomended?
I have seen various posts of putting twin pumps in the tank? how on earth do i go about doing this? trust they have to be in parallel? - a bit too much involved when i can buy a bigger Bosch 044 8bar motorsport pump?
and what do i need to do to fit one? hard to do? - the car is daily transport so cant go about hacking bits off it if you know what i mean ;-)
what pressure do i need to set one at? is there a pressure regulator standard on the hsv?
Questions Questions Questions.....
any thoughts please?
i have fitted a CF supercharger to a 5.7 ls1 and think that the fuel pump is now the weak link? 340bhp now up to 530bhp
what type of pump is recomended?
I have seen various posts of putting twin pumps in the tank? how on earth do i go about doing this? trust they have to be in parallel? - a bit too much involved when i can buy a bigger Bosch 044 8bar motorsport pump?
and what do i need to do to fit one? hard to do? - the car is daily transport so cant go about hacking bits off it if you know what i mean ;-)
what pressure do i need to set one at? is there a pressure regulator standard on the hsv?
Questions Questions Questions.....
any thoughts please?
ask a guy on here called stevieturbo (i think). he has a LS1 putting out about 750bhp (rear wheel) and should beable to give you some advise!
also you might want to speak to boostedls1 on here!
he does a lot of work with the LS1 and might beable to advise you on a good setup.
one thing that i have seen form looking into these realy good engines is if they go lean and dept, your in VERY big trouble!!!!!!!!
thanks Chris.
PS. sorry i couldn't be of more help!
also you might want to speak to boostedls1 on here!
he does a lot of work with the LS1 and might beable to advise you on a good setup. one thing that i have seen form looking into these realy good engines is if they go lean and dept, your in VERY big trouble!!!!!!!!
thanks Chris.
PS. sorry i couldn't be of more help!
In all honesty, I am sceptical about this, as I'm sure has been apparent from myself and others over on the other forum.
I would be extrememly worried that both pump, AND injectors are beyond their safe limits.
First off, I am not directly familiar with either fuel tank setup on the 2 Holden cars as I havent personally seen it, but I have an idea of what they are like.
One problem though, is that your car uses a dead end system. There will be some form of regulator in the tank, which complicates matters a little.
Most popular upgrade would be a simple in-tank Walbro which would be quite happy at 530bhp or thereabouts, retaining the factory fuel lines etc.
I'd also reccomend larger injectors. 42lb Ford SVO items can be bought very cheap.
This is an easier route, as the Walbro is a small pump, designed for in-tank mounting ( its size also makes a dual installation that liottle bit easier. )
If you wanted to push this a little further, you could add a "BAP" Boost a Pump, which is a voltage booster, usually controlled by a boost switch. The yanks seem to like these, although Ive never heard of them used over here.
I think Racetronix in the US might do a plug n play upgrade for a Pontiac GTO with a Walbro based pump ??
You could mount a Bosch 044 in-tank, but its a lot bigger, and would need some sort of gauze pickup installed.
I think Bosch do an 040 which is supposedly a dedicated in-tank unit, although not quite as capable as the 044 in-line ( which can also be used in-tank )
If you want to add an inline pump, you will need to upgrade toa return style system, with a fuel pressure regulator up front. You can either boost reference this, or just leave at at 58psi with no boost/vac reference.
Again, Walbro do a nice good value in-line, on par with their in-tank unit.
The 044 would be better again, with a price tag to match.
You should think about your power goals, and how much fuel system you will need, before taking the plunge and making the upgrades.
I was in a better position, as mine was built from scratch. I used 2 "044" pumps running in parallel, with a 1/2" hardline tube for the feed, splitting to 2 -6 lines to each Aeromotive fuel rail, then tee-ing together and into a Magnafuel regulator, and back to the tank via a 3/8" hardline tube.
I was using a set of Siemens 660cc injectors at 4.5 bar base + 1:1 boost ref. These were pretty much maxed out circa 5000rpm but AFR's were holding safe and in control despite this.
I have since upgraded to a set of RC Eng 73lb injectors, although for some strange reason, they have made little difference to actual inj opening times to achieve the same AFR's and this is still running with 4.5 bar base pressure.
The Bosch pump excells above others at high pressures, which is why I chose it. I wanted a system where I could up the pressure, to overcome flow limits with the injectors.
I wanted a fuel system safe for in excess of 1000bhp, which it appears I have, despite the injectors not quite being up to the task.
Once you do sort out your fuel system, next matter is getting someone to re-map everything to suit.
You should also ask over on LS1Tech.com or on Ls1gto.com
There will be pictures of upgrades others have done.
Most dual upgrades will have a 2nd pump, jubilee clipped to the first, with fuel line-s simply tee-d together.
re-wiring is a wise idea, as the factory wiring was never intended to carry double the current.
I would be extrememly worried that both pump, AND injectors are beyond their safe limits.
First off, I am not directly familiar with either fuel tank setup on the 2 Holden cars as I havent personally seen it, but I have an idea of what they are like.
One problem though, is that your car uses a dead end system. There will be some form of regulator in the tank, which complicates matters a little.
Most popular upgrade would be a simple in-tank Walbro which would be quite happy at 530bhp or thereabouts, retaining the factory fuel lines etc.
I'd also reccomend larger injectors. 42lb Ford SVO items can be bought very cheap.
This is an easier route, as the Walbro is a small pump, designed for in-tank mounting ( its size also makes a dual installation that liottle bit easier. )
If you wanted to push this a little further, you could add a "BAP" Boost a Pump, which is a voltage booster, usually controlled by a boost switch. The yanks seem to like these, although Ive never heard of them used over here.
I think Racetronix in the US might do a plug n play upgrade for a Pontiac GTO with a Walbro based pump ??
You could mount a Bosch 044 in-tank, but its a lot bigger, and would need some sort of gauze pickup installed.
I think Bosch do an 040 which is supposedly a dedicated in-tank unit, although not quite as capable as the 044 in-line ( which can also be used in-tank )
If you want to add an inline pump, you will need to upgrade toa return style system, with a fuel pressure regulator up front. You can either boost reference this, or just leave at at 58psi with no boost/vac reference.
Again, Walbro do a nice good value in-line, on par with their in-tank unit.
The 044 would be better again, with a price tag to match.
You should think about your power goals, and how much fuel system you will need, before taking the plunge and making the upgrades.
I was in a better position, as mine was built from scratch. I used 2 "044" pumps running in parallel, with a 1/2" hardline tube for the feed, splitting to 2 -6 lines to each Aeromotive fuel rail, then tee-ing together and into a Magnafuel regulator, and back to the tank via a 3/8" hardline tube.
I was using a set of Siemens 660cc injectors at 4.5 bar base + 1:1 boost ref. These were pretty much maxed out circa 5000rpm but AFR's were holding safe and in control despite this.
I have since upgraded to a set of RC Eng 73lb injectors, although for some strange reason, they have made little difference to actual inj opening times to achieve the same AFR's and this is still running with 4.5 bar base pressure.
The Bosch pump excells above others at high pressures, which is why I chose it. I wanted a system where I could up the pressure, to overcome flow limits with the injectors.
I wanted a fuel system safe for in excess of 1000bhp, which it appears I have, despite the injectors not quite being up to the task.
Once you do sort out your fuel system, next matter is getting someone to re-map everything to suit.
You should also ask over on LS1Tech.com or on Ls1gto.com
There will be pictures of upgrades others have done.
Most dual upgrades will have a 2nd pump, jubilee clipped to the first, with fuel line-s simply tee-d together.
re-wiring is a wise idea, as the factory wiring was never intended to carry double the current.
Edited by stevieturbo on Wednesday 30th August 21:23
Each 044 is good for about 350-400bhp static in our experience (2000bhp Superflow 901 dyno with 044 pumps.) You'll need two to maintain constant pressure at your power level. In our experience of high power turbo systems (we have built / dyno'd 1800-2000+ bhp V8's) your fuel system would work best with a lift pump from the tank (low pressure) to a swirl pot feeding two 044's. A return line from an Aeromotive 13109 regulator into the swirl pot, and a return from the swirl pot into the fuel tank.
This system has worked well in many EFI V8 cars for my clients.
This system has worked well in many EFI V8 cars for my clients.
p15ton said:
your fuel system would work best with a lift pump from the tank (low pressure) to a swirl pot feeding two 044's. A return line from an Aeromotive 13109 regulator into the swirl pot, and a return from the swirl pot into the fuel tank.
This system has worked well in many EFI V8 cars for my clients.
This system has worked well in many EFI V8 cars for my clients.
I though the 044's were good for at least 500bhp each. I'm running a single 044 on 5.7 low boost setup, which is a little over 400 bhp i guess.
Anyways, here's some piccies of dual 044's with lift pumps as described by Peter.
http://homepages.nildram.co.uk/~eliot
http://homepages.nildram.co.uk/~eliot
p15ton said:
Each 044 is good for about 350-400bhp static in our experience (2000bhp Superflow 901 dyno with 044 pumps.) You'll need two to maintain constant pressure at your power level.
Odd.... That would seem to contradict what many others have achieved both in the UK and around the world. Numbers may of course vary from place to place, but the 044 is recognised as 5-600bhp+ capable in efi form anywhere I have heard of it used.
If 1 is only capable of 400bhp, than I'd be a little concerned.
I used 2 in parallel, I am making around 800rwhp ( so guess 900+ or so flywheel ?? ) running at 4.5 bar base + up to 1.3 bar boost, so 5.8bar pump pressure being used.
My fuel pressure is rock solid.
I know that the little Walbros are capable of 500+ dependant on pressure used, and the 044 is far more capable.
Both dyno usage for many EFI & turbo engines & Data logging from Enduance GT cars indicates that about 400 bhp per pump is about it. Anything above 400 bhp requires both pumps to maintain constant fuel pressure without fluctuation. Our system uses a 500 GPH lift pump, so fuel to the swirl pot is not an issue through -10 lines (!) I have been using systems like that for six years, so I have plenty of data.
What makes it even stranger, is that in the US, they claim to have a 420lph Bosch pump, and some LS1 users have pushed this to circa 700rwhp.
I tried very hard to get a part number for this pump, but struggled anywhere I asked. one person did answer and they said it was indeed an 044 too. Al the vendors who sell them, wouldnt give me a part number, or confirm if it was an 044.
I know US HP figures do tend to be that bit higher than UK or anywhere else in the world, but every bit of info Ive ever seen would indicate that one is capable of a LOT more than 400bhp, including my own direct experience.
I tried very hard to get a part number for this pump, but struggled anywhere I asked. one person did answer and they said it was indeed an 044 too. Al the vendors who sell them, wouldnt give me a part number, or confirm if it was an 044.
I know US HP figures do tend to be that bit higher than UK or anywhere else in the world, but every bit of info Ive ever seen would indicate that one is capable of a LOT more than 400bhp, including my own direct experience.
You at 800 bhp are OK on two 044's.
Would you want to run your injectors @100% duty cycle? No. So you don't want to run your pumps at max. capacity either. One pump IS NOT good at 600bhp FOR CERTAIN, with a SAFETY MARGIN.
Sorry, I am used to being asked for what works, not what you can get away with.
Would you want to run your injectors @100% duty cycle? No. So you don't want to run your pumps at max. capacity either. One pump IS NOT good at 600bhp FOR CERTAIN, with a SAFETY MARGIN.
Sorry, I am used to being asked for what works, not what you can get away with.
That is 800 hp at the wheels, supercharged application, so actual engine figure will be higher.
And I am nowhere near a safe 80% IDC lol. My ecu wont drive low impedance injectors, so I cant run the size I actually need, hence I am using smaller ones, at much hgher pressure, as well as pushing them pretty much to 100% IDC.
AFR's are still under control, and hopefully with my new inlet manifold arrangement, I can make another 50-60bhp
And I am nowhere near a safe 80% IDC lol. My ecu wont drive low impedance injectors, so I cant run the size I actually need, hence I am using smaller ones, at much hgher pressure, as well as pushing them pretty much to 100% IDC.
AFR's are still under control, and hopefully with my new inlet manifold arrangement, I can make another 50-60bhp
chuntington101 said:
what are you going with steve?? fast or a custom one???
Chris.
PS. what superharger brakety did you use?? what was it intended for??
Chris.
PS. what superharger brakety did you use?? what was it intended for??
It was Holden based, or now same as Pontiac GT0, although I ended up getting all my own pulleys made instead.
Not an actual carburettor of course....that would be bloody daft !!!!
Something like this
Edited by stevieturbo on Saturday 2nd September 20:45
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