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Might be a dumb question, but that's never stopped me before....

 

does anyone use fuel cell foam in an oem fuel tank?  The spyder fuel starves in long right handers with as much as 1/4 tank of fuel.  It is a baffled tank, but it doesn't take long enough for the fuel to migrate away from the partition with the pickup.  I figure some fuel cell foam stuffed through the access hole for the in-tank pump is easy to do and might help.....

 

Thoughts? 

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WTB: CSP Spyder parts. What you got?

I think you have hit a RAW NERVE with a lot of the "STOCK " Class solo cars that are as they say" prepped. "   The silence you hear from people is your answer. I know a lot of the stock lotus Elises ,  and C4 vettes run real light on fuel load and they have all solved the cutting out on corners problem without carrying a full factory size tank of fuel. You see them adding 2 quarts of gas between runs. It obviously works and, UHH, Yes they cheat.

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Doug Maxcy
Viper SRT-10 , SS 88
ASP Nat. Champion, JPS Lotus Europa

I'm running CSP where foam in the stock tank is allowed.  If the foam will help even a little bit without hurting anything then I have no need for a fuel cell. The stock tank is in an ideal location (as low as possible, and just about dead on the front-rear CG plane.)  The stock tank is light.  The car is still driven on the street to events etc, and an 12 gal tank is nice to have.

 

I'd rather not take silence to mean anything but a lack of response.  Without pointing fingers or naming names, are you saying you are assuming it works, or that you know it works?  Assuming is fine if you personally aren't going to be stuffing foam in your fuel tank as a result of the point... :-)

I don't know about stock class people cheating and I'd prefer to take an optimistic view on the subject, but can anyone say that this will help my problem and not cause any issues, or alternately say that people who have tired it have issues like______, etc?

 

Thanks for the response,

Richard 

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WTB: CSP Spyder parts. What you got?

As long as you fill it all the way and not interfere with the sender, it should work very well for quick transitions. Mind, though, in a very long sweeper, you may well continue to starve because the foam is there to prevent sloshing and dramatic weight transfer, not entirely stop the flow of fuel, but to restrict it some.

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James Plotkin
'05 FSP Echo

We tried it in our DSP car. It didn't work as I had planned since the shape of the tank was just too wrong to begin with. We use the open rule for fuel plumbing and have added a small pump from the other side of our tank, which has it's own secondary pickup from the factory, and extended the return line into a small surge box surrounding the main pump.

From the factory, our secondary pickup tee's into the return line with a fancy "jetpump" valve to siphon fuel from the other side of the tank as the main return line does it's thing. The problem is that once the main pump starves, the pressure drop isn't enough to adequately siphon fuel from the other side. The small secondary pump ensures a constant flow from the other side that continuously fills the surge box, keeping the main pump supplied at all times.

Prior to this, we were experiencing fuel starve at anything below 3/4 tank. Now we can run lower than 1/4 and be safe. E36 BMW's have this issue as well, but the secondary pickup has the same mounting rim (to the tank) as the main pickup, making it easier to add a second pump to keep the engine happy.

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Jay Storm
96 Impreza L FSP
98 98 Impreza 2.5RS- co-driver DSP
Wives are like SCCA rules...
If she doesn't say you can...you can't

I wouldn't expect the foam to help with fuel starving at all.  Fuel cell foam is intended to keep the gasoline from exploding in the event that the tank gets ruptured and an ignition source is present.  Basically, it can slow the flow of the gas down when dealing with extremely fast flow rates (ie- exploding).  When it comes to slowing the flow of fuel during a cornering event, it isn't going to have any noticable effect.  I had fuel starving problems with my car for years - always just ran it full.  When I swithced to a 4gal fuel cell with foam, I hoped I would be able to run it pretty low, but it turns out that it will still starve at anything less than about 2/3 full, so I still have a very limited working range (approximately 1.5gal between full and potential to starve).  If you've ever watched someone fill a foam filled fuel cell, you will see that the foam really doesn't restrict the flow of fuel at all at normal flow rates.  Building an internal or external surge tank is a smarter way to go, and likely safer too.  Engineering the installation of a fuel cell is not a trivial task. 

 -Chris 

D.W. Maxcy:

I think you have hit a RAW NERVE with a lot of the "STOCK " Class solo cars that are as they say" prepped. "   The silence you hear from people is your answer. I know a lot of the stock lotus Elises ,  and C4 vettes run real light on fuel load and they have all solved the cutting out on corners problem without carrying a full factory size tank of fuel. You see them adding 2 quarts of gas between runs. It obviously works and, UHH, Yes they cheat.

 

Just supply the boroscope and I'm sure you can get your theory proven or disproven.