I semi disagree with the amount of flow needed. I have a surge on my race car now. With a surge you basically have two fuel systems so the pump that feeds the surge tank only needs to fill that up slowly and keep it topped off. So any pump that would keep it full would work. Now on the injector side you need the high pressure pump to feed the injectors at a constant pressure at different volumes. I think we all get this. The low pressure pump to keep the surge full does not really need to keep it totally full as you can run a good lap or two without it filling up as it has enough fuel for the injectors. Now after the main tank runs dry under braking or a turn then the lp pump will fill up the surge. It does not need to be big at all, just enough to keep the surge basically full. The bigger pump works, but will draw more amps and cam be overkill. Just my thought on it.
Surge Tank
- Thread starter Troymx576
- Start date
Troy I am new to the forum but have owned my SL-C since 2009. I recommend that before you mount anything that you drop in the engine and gearbox, then start to locate all the items you are going to put into your car, surge tank, oil coolers electricals oil tank, all the main items. At that point you mark all the items for where you will locate them from there you figure the plumbing for each item of where you will try to run them. Then you pull all the stuff back out of the car and start to mount all items, once completed route the plumbing since a lot of the plumbing will get in the way of the rest of the plumbing, once this is completed place the engine back in the car and hook up along with the gearbox. Then you can fine tune the plumbing. With the engine out of the car it is easier to get to everything to mount and plumb. Keep in mind the plumbing needs to be routed as far from the exhaust as possible. I also wrapped all the oil lines and shift cables in insulation from Summit to include the cloth type wrap held in place with tie wire then the silver tube insulation over that. I have been going through the problems with the fuel pump and surge tank also. I burned up a transfer pump, 2 HP pumps. I went to Aeromotive tech guru and sent them a complete diagram of the fuel system along with pictures. We found out the HP was cavitating even though it had the surge tank. We replumbed the fuel system as follows
fuel tank to 40 filter to transfer pump to surge tank to HP to 10 filter to engine to regulator to surge tank. We ran all #10 lines except from regulator to surge tank was a number 8 and from surge tank to fuel tank #8. The cavitation was caused from the line from the surge tank to the HP was too long. We rerouted the line so that all lines except the line from the HP to the engine are less than 1 ft long.I hope some of this info will help.
Bob D
fuel tank to 40 filter to transfer pump to surge tank to HP to 10 filter to engine to regulator to surge tank. We ran all #10 lines except from regulator to surge tank was a number 8 and from surge tank to fuel tank #8. The cavitation was caused from the line from the surge tank to the HP was too long. We rerouted the line so that all lines except the line from the HP to the engine are less than 1 ft long.I hope some of this info will help.
Bob D
Out of curiousity why the need for -10 line to feed the engine? Even my engine is just -10 from the fuel tank to the pump, then -8 engine feed/return.
Alex It originally had 10 line and Aeromotive tech dept said had to be a minimum of 8 line, I stuck with the 10 line figuring more volume to help when it sucks down the surge tank in a turn, also since we were having cavitating problems I wanted as much fuel to the HP pump as possible so it did not happen again
Interesting - everything I"ve learned from fuel pump manufacturers (e.g., Weldon) is that if you use too big a line to your engine that it doesn't need (e.g., -10 from the pump to the fuel rails in a 500hp application) you can actually do harm to it. But then again I'm not going to pretend that I know anything about surge tanks so I just find this interesting, that's all 
Alex I do not know anything about the fuel system required either. Mine is pushing 625 Hp and I did ask the Aeromotive guy about the fuel line and told him what we had and he said it was fine. because of the problem with the fuel pump, he wanted every detail about the system along with pictures etc. and according to him I am now good to go. I will let you know if we have another fuel pump failure. It is these forums that I think all of us SL-C guys face the same problems and I am glad I am on here finally so people can compare problems how someone handled the problem compare what works and what doesn't. Fran may not like all I talk about here but i can tell you if we are all not sharing the problems we are having we will all go through the same learning curve which is a lot of time and money when someone else faced the same problem fixed it and shared it so now we all know what to do to get a great dependable car. I love my car and it is as fast as I want to go, which is 230mph if possible I just need to find the place to do it.
Bob...
I have no problem with guys discussing their builds at all....Good/bad or indifferent...thats what these places are for...collective learning.....but keep in mind that you purchased a pre built car from a guy that forgot which end of the wrench to use as a hammer....
Welcome to the forum and have fun
I have no problem with guys discussing their builds at all....Good/bad or indifferent...thats what these places are for...collective learning.....but keep in mind that you purchased a pre built car from a guy that forgot which end of the wrench to use as a hammer....
Welcome to the forum and have fun
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Ian Anderson
Lifetime Supporter
We run two walbro lift pumps and two 044 HP pumps on the 01 car...we have a redundant pair that are switched due to any on track failure....as yet no fuel pump issues...
Bob, thanks for the tips and info and that does make sense. Me having one on order has me thinking about it and wanting to do something before it comes in. I am just gathering parts and items now so when I get the kit it will be as much work on the car instead of researching for hours on the net, then ordering parts and waiting.
On the pumps here is a thought. I have been running a surge and setup in my race car, now not as fast or high hp as an SLC, but same basic thing for the last year and has about 10,000 track miles on it. This has been a great setup in our MR2 and has solved the surge and we never have an issues with it.
Setup
Stock tank with in tank pump
pump is an Mr2 turbo high pressure pump
goes through fuel filter, stock
dumps into surge tank
Fill surge and then back into return to stock tank
Surge tank bottom to about 4" of 6an to 190lph high pressure pump
6an out to fuel rails
6an out of fuel rails to fuel pressure regulator
fuel pressure reg drain into surge tank
Surge tank is only 1/3 gallon
This works good. With the fuel pump in the main tank you can hear it working when feeding the fuel rails before the surge install. Now it just humms quietly working on putting fuel in the surge tank.
So here is my question. Why use a low pressure pump like the Holley 12-125? Can we just not use something like a Walboro 190lph external pump and it would flow more than enough to fill that surge tank? Then if it ever goes dry it can run dry for a little bit, this I have tested. And if it does not have fuel for a bit when it does it should fill it up really fast as it can flow a lot more volume when not under pressure. I was wondering why lower pressure pumps for transfers like this when the system is basically open it will not build up pressure so the high pressure pump becomes a low pressure pump.
My setup that is planned so far
Stock tank with 8an fittings
8an out of tank
8an fuel filter 40-100 micron ss
transfer pump
6an outlet
6an into upper part of surge tank
8an out of top of surge tank-overflow drain into top of main tank
8an botton of surge
8an fuel filter 10 micron
bosh 044 high pressure pump
6an to fuel rails
6an T to feed both fuel rails front side
6an out of backside fuel rails
6an to T to make one line
6an to fuel pressure regulator
6an out of fuel pressure regulator to top portion of surge tank
I can change all the fittings and sizes to 8an and now Bob has me wondering if that is even a good idea. The Bosch 044 should be able to handle the pressure and volume of the 6an line and if that helps with the pumps then good.
On the pumps here is a thought. I have been running a surge and setup in my race car, now not as fast or high hp as an SLC, but same basic thing for the last year and has about 10,000 track miles on it. This has been a great setup in our MR2 and has solved the surge and we never have an issues with it.
Setup
Stock tank with in tank pump
pump is an Mr2 turbo high pressure pump
goes through fuel filter, stock
dumps into surge tank
Fill surge and then back into return to stock tank
Surge tank bottom to about 4" of 6an to 190lph high pressure pump
6an out to fuel rails
6an out of fuel rails to fuel pressure regulator
fuel pressure reg drain into surge tank
Surge tank is only 1/3 gallon
This works good. With the fuel pump in the main tank you can hear it working when feeding the fuel rails before the surge install. Now it just humms quietly working on putting fuel in the surge tank.
So here is my question. Why use a low pressure pump like the Holley 12-125? Can we just not use something like a Walboro 190lph external pump and it would flow more than enough to fill that surge tank? Then if it ever goes dry it can run dry for a little bit, this I have tested. And if it does not have fuel for a bit when it does it should fill it up really fast as it can flow a lot more volume when not under pressure. I was wondering why lower pressure pumps for transfers like this when the system is basically open it will not build up pressure so the high pressure pump becomes a low pressure pump.
My setup that is planned so far
Stock tank with 8an fittings
8an out of tank
8an fuel filter 40-100 micron ss
transfer pump
6an outlet
6an into upper part of surge tank
8an out of top of surge tank-overflow drain into top of main tank
8an botton of surge
8an fuel filter 10 micron
bosh 044 high pressure pump
6an to fuel rails
6an T to feed both fuel rails front side
6an out of backside fuel rails
6an to T to make one line
6an to fuel pressure regulator
6an out of fuel pressure regulator to top portion of surge tank
I can change all the fittings and sizes to 8an and now Bob has me wondering if that is even a good idea. The Bosch 044 should be able to handle the pressure and volume of the 6an line and if that helps with the pumps then good.
There are a couple of reasons for a LP pump from the tank to the swirl pot.
One of them is that HP pumps like the Walbro and the 044 tend to burn up when run dry. The LP pumps design tends to be less sensitive to that kind of abuse.
Second, they are also high-volume, low pressure pumps, which is just what the swirl pot wants, as opposed to high-pressure fuel coming into the pot which would tend in increase foaming and aeration rather than decrease it.
You've been lucky with running a HP pump dry for a little bit- that kind of use tends to make them burn up quickly. I bet if you put that pump on a test rig you'd see reduced performance after running it dry for much time.
Marc, Fuel injected engines and HP fuel pumps get cranky when they are not being fed. When the fuel tank gets down to the 1/4 tank, race car, street car doesn't matter, you can start to have problems with cavitation, usually under acceleration, or cornering. This is just insurance to make sure there is always fuel being supplied to pump and engine.
Double post
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Re: Surge Tank <hr style="color:#DEEDF2; background-color:#DEEDF2" size="1">
You may not depending on fuel demand (hp). All production cars use a in tank pump system. The pump is located in the bottom of the tank, so becomes the lift/pressure pump in one, has attached pre-filter screen.
Benefits are the pump is cooled by the fuel, less plumbing, components.
Can have integrated pressure regulator, so 1 line output to filter & injectors.
Disadvantage is adapting to custom tank.
less serviceable. Flat bottom tank would need internal collection box
http://atlinc.com/pdfs/Racing/2012-ATL-RACING-CATALOG-web 19.pdf
You may not depending on fuel demand (hp). All production cars use a in tank pump system. The pump is located in the bottom of the tank, so becomes the lift/pressure pump in one, has attached pre-filter screen.
Benefits are the pump is cooled by the fuel, less plumbing, components.
Can have integrated pressure regulator, so 1 line output to filter & injectors.
Disadvantage is adapting to custom tank.
less serviceable. Flat bottom tank would need internal collection box
http://atlinc.com/pdfs/Racing/2012-ATL-RACING-CATALOG-web 19.pdf
Marc,
Admittedly, using a surge tank increases the complexity a bit but if an in tank pump fails I'd hate to be the one to have to replace it.
There are some pretty good diagrams on how to lay out the surge pump as well as discussions on what specific LP and HP pumps people are using (Bosch 044 seems a common choice). After studying the diagrams, it's relatively straightforward. Of course, I've yet to start mine.....
Admittedly, using a surge tank increases the complexity a bit but if an in tank pump fails I'd hate to be the one to have to replace it.
There are some pretty good diagrams on how to lay out the surge pump as well as discussions on what specific LP and HP pumps people are using (Bosch 044 seems a common choice). After studying the diagrams, it's relatively straightforward. Of course, I've yet to start mine.....
Ken Roberts
Supporter
I have built a surge tank to install but might not use it if my intank factory GM bucket works out. I'm using a fuel pump module from a 2002 Camaro. It has a Walbro 255 pump installed in it. The bucket is always kept full no matter what the level of fuel is in the tank. They have a venturi pump in the bottom of the bucket that continually draws in fuel to keep the bucket full. As long as there is enough fuel in the bottom of the tank to cover this venturi then it will keep the bucket full. It looks as if the bucket will hold at least a liter of fuel. The Walbro pump has a seperate small orifice and fuel line than sends a small amount of fuel under pressure to the bottom of the bucket for the venturi pump.
The top of the tank has to be cut down a bit to make it wider to accept this type of fuel bucket module. The other benefit is that the module has a built in vent system and fuel pressure sensor for my EVAP system. It also has a built in fuel regulator as well. I might gut it though and run a C5 Corvette fuel filter/regulator in the engine compartment for ease of servicability.
The top of the tank has to be cut down a bit to make it wider to accept this type of fuel bucket module. The other benefit is that the module has a built in vent system and fuel pressure sensor for my EVAP system. It also has a built in fuel regulator as well. I might gut it though and run a C5 Corvette fuel filter/regulator in the engine compartment for ease of servicability.
I wound up getting the 044 Bosch for pressure side, the Holley 125 to fill the surge tank and decided togo with 6an feed lines to and from the fuel rails. I will only have like 250hp AN and 500-550 twin turbo so that will be fine.
I wound up buying a surge tank for $70. I was going to make one, but the fittings are like $5+ each, plus shipping and materails to make it were about $20+ shipping. So it basically would cost about the same. And for fitment, when I see people sticking a 500gallon dry sump oil tank here and there I am not all that concerned with finding a place when I am only using a V6 that is super compact (LS3 28.75" long 3mz is 20.5" long, 23 tall vs 28 tall, 22 wide vs 24.75 wide) . I have lots of room to play.
I wound up buying a surge tank for $70. I was going to make one, but the fittings are like $5+ each, plus shipping and materails to make it were about $20+ shipping. So it basically would cost about the same. And for fitment, when I see people sticking a 500gallon dry sump oil tank here and there I am not all that concerned with finding a place when I am only using a V6 that is super compact (LS3 28.75" long 3mz is 20.5" long, 23 tall vs 28 tall, 22 wide vs 24.75 wide) . I have lots of room to play.
