As I continue to plan out my build/updates, I've considered going to a surge tank in the front of the car to prevent and fuel starvation and/or be able to use the full 16.4 gallons (plus whatever is in the surge tank ).

My car probably won't ever see true slicks, but it still corners pretty hard, enough to slosh fuel away from the pickup I'm sure. I'm just curious if anyone else has ever felt the need for a surge tank in their cars, or has any particular tips/tricks before I begin my designs?

Thanks! Happy race season.

I've used one since 2005
I can drain the cell down to a cup of fuel

now a days, there is a really neat/amazing pick up matt that will do the same thing. its not cheap, but easy to install with no additional fittings.

surge tanks are mandatory on 914 race cars with fuel injection
I did it on a carb'd car to save weight by being able to routinely run short sessions and go out with only 4 gallons in the cell

you can make them yourself, mine was an aluminum oil accumulator with aluminum fittings welded on

brant

Yeah the Holley Hydramat is pretty cool. But a surge tank accomplishes the same thing, and at least in these cars, isn't too much work. Just needed the go-ahead from an established racer like yourself Brant. The accumulator was sort of the direction I was planning to go. Thanks!

I've got a few plumbing pictures in my build thread
its been a great system and no pick up problems as a result

I have a swirl pot sitting in the garage...no need (even on slicks) on my current build. I doubt you will need one...just sayin.

Tony

We mounted one in the fuel cell of The Beast. It worked great. Couple of pictures follow:

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I have one of the in-tank models like Randall. When I first built my 914 racecar I didn't use a surge tank (I have a 12 gallon ATL tank), and I had starvation on two different occasions when the tank was half full. After that, I filled up for every session, and was OK since I never really run sessions longer than a half hour. Definitely recommend a surge tank.

Scott

if you are running FI I would consider running a surge tank in the rear.
My logic is the high pressure FI lines will be shorter and fewer connections to potentially fail.

Any heard of using a snowmobile pickup. I think a friend of mine using them for his track car. (LS powered Mazda RX-7)

Good info guys, thank you.

Yep, in this setup, it'll be EFI. My plumbing idea thus far is actually
tank->
low pressure pump up front->
surge tank up front->low pressure line back through the tunnel->
high pressure external pump on lower firewall->
engine->
return to tank.

That still eliminates the long length of high pressure lines that Mark was alluding to, but also still allows me to stuff a type 4 back into the car if I had to. In this case, the low pressure pump would also be a "lift" pump up to the surge tank, and gravity/pressure within the sump would feed the fuel back to the high pressure pump.

In Chumpcar we don't need a fuel cell if the stock tank is retained, but I sure would like to go the fuel cell route, especially as it would make routing the water lines easier through the front bulkhead. Just need to save my pennies.

Shane, I have not heard of people using the snowmobile pickups, but that's the same concept as the Holley Hydramat (just cheaper). I HAVE heard of a cool one though - some folks use a large Yamaha marine fuel filter which also acts as a surge tank of sorts. Pretty cool idea. I think this is the one I heard them talking about.

I realize I stand alone here on this one but I still contend that you will not need the surge tank. Just plumb your HVLP pump to your HPFP and return off the fuel rail or regulator. You said you're not running slicks...correct?

I have had no issue with fuel starvation and am running just off Cup car pace on slicks. However, it sounds like you "want" a surge tank - they do look cool. If anything, I'd consider adding one of those Holley mats mentioned before for a bit of extra measure.

T

Tony, the main concern is being able to use the entire fuel capacity as we are endurance racing. Im not sure you've run the tank down enough to need it? I could be wrong though.

I wonder how long 16 gallons will last with your new engine? Even if your getting every last drop do you think it will be longer then an hour?
Thinking a 22 gallon fuel cell might be the ticket.

Yeah, I think so too Shane. I'm betting closer to 1.5 hours, but still not enough. The rules state we can go as large as 2 gallons over stock - and realistically, as much as a stickler as I am for safety, it should have a cell anyways. At this point it comes down to race car versus diapers, but we all know that diapers win out everytime. Love that little guy.

Surge tanks are pretty easy to do.

SDS uses a simple tube with plates welded on and a few bung fittings, very simple very well thought out.

Or you can do the rock crawler design which uses a filter much like the unit above. I had originally thought about using this on my car and have since gone back to SDS style unit.

Gravity feed to the pump is always better than a suction feed. I am sure they both work well. I am just choosing not to go against a force of nature.

SDS design

Rock Crawlers Surge Tank built out of a fuel filter.

You can increase the fuel filters surge tank capacity by using one of these kits. It even has a fuel petcock at the bottom of the filter to drain off water, or can be used a fuel sample port if you series requires that sort of thing. I figured in my case running E85 this would allow me to get some water out of the system.

So my setup now goes like this:

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A - Stock Fuel Tank
B - Pre Filter
C - High Volume Low Pressure Fuel Pump
D - Fuel Filter Water separator
E - EFI Fule Pump
F - Engine fuel injectors / Pressure regulator
G - Fuel Surge tank

Pretty simple, as along as I bring some fuel with me to the events, I can run ultra low fuel levels in the tank, 1-2 gallons and do my runs. That shaves 20 to 112 pounds of weight off the car! For an auto-x run well worth it!

George - Not sure if you are planning on a fuel cell, but we were able to find an ex-nascar 18 gallon cell - used steel can with a new bladder pretty cheap on eBay. Basically, it allows us to run 18 gallons + the 1/2 gallon surge tank:)

Thanks Andrew. As said, things are at a little bit of standstill with family matters at the moment, plus the Chumpcar rules being all up in the air. I thought that HeaterGuy's thread was interesting, because I had never considered running the car in SCCA, but ITE is a possibility. If I did so, it would definitely get a fuel cell. I like the NASCAR cell idea. I'll keep a look out.

-G

I think I'm not following how a fuel filter can act as a surge tank. I get that fuel can accumulate there, but unless there is a second fuel pump in the circuit pulling the fuel from the filter, you'll still lose pressure if the main fuel pickup in the tank starts sucking air. Maybe I'm missing something though ...

Scott

Surge tabks do require two pumps. One low pressure carb pump to prime the surge tank and then your primary pressurized pump.

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Well. I caved and added a swirl to my system today. Everything works well and there definitely is less stress on the low pressure pump. I'm glad I did this...

Tony

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Very impressive Tony. Now you have to explain the plumbing and all the functions of that "swirl" tank.

Randal - Thank you. I'll let you do the honors...

T

You are way ahead of me on this one Tony.

I helped with the surge box in The Beast, but that was not near as complicated as a "swirl" system you built (from scratch). And I must say your fabrication skills, as displayed on your DSR and 914-8 are exceptional.

I did find some good documentation on how swirl system work, but not sure if this is the same as what you've built. Anyway, Google again proves to be your friend:

http://www.nukeperformance.com/technical-i...flow-chart-faq/

Interesting stuff - I may need to take a crack at this sometime as well. I have had some mild starvation sometimes at low cell levels and I do the same thing where I only fill 4-6 gals for a 20-30 min session.