Lotus Elan Fuel Cell, Possible Group Buy

[tvacc]

Hi all,

I need to buy 2 fuel cells for my Elans. I prefer having a fuel cell to the standard metal tanks. I have done this before and they would be a bladder with foam and a flipover valve in an aluminum can the same shape and size of the original (might be 1 inch lower to allow us to put a plywood top over the cell. I also would have a fuel sender unit and a another way to measure the fuel with a rod that you would pull in and out. Tanks would be vented as well.
Cost will be between $1500 and $1900 depending on how many we order. I would order them from Harmon Racing Cells. I have bought cells from him in the past and they are great people to work with. I assume this would be for those in the states as that is where I am and Harmon is. If anyone is interested please email me at tvacc*at*lotusowners*dot*com. Not going to make any money here, we will all pay the same price. I need at least 2 more to get a price break of about 10%-15%,

[Frogelan]

Tony, I think that your idea is very good, as a proper bag tank would also improve impact protection.

Here in Europe FIA rules would require the fuel bladder to have a steel container in a fibre glass car. It would also have a limited lifetime.

I would be interested to know more about your project, especially as my car is LHD, but I suspect that our rules and the import costs may make it rather. I had in mind a similar project with a single 60 litre tank (15.85 US gallons and 13.2 GB gallons) for my project, but I have not got beyond some initial calculations.

[tvacc]

You bring up a curious variant to my group buy.

Today with modern tires and emergency tire inflators is it really necessary to have a spare tire? I have often thought of putting a larger tank in the boot with the larger section going where the spare tire is/was located.

When is the last time you changed a tire and used a spare? Hey, if you or any of you want to consider a 13 or 15 gallon cell in the Elan, I am up for it. We could get it custom made to fit right across the bottom under the wood and you would not even see it. It would look like a normal Elan but you would increase your range by almost double.

Of course you do add weight of 7lbs or so per gal.

Perhaps we could somehow make a model out of foam or something of a tank that fills up the whole bottom of the boot. Would love to get others opinions, good or bad on this.

[tvacc]

Oh this cell would be an aluminum can with a bladder inside. with foam in the bladder.

[USA64]

I have thought about a bladder tank with some sort of dry-break inlet/outlet and might consider buying in even though I have a brand new alloy tank on the shelf. Questions: the foam is for anti-surge for racing I think, how would it behave with old gas? Can one clean a bladder tank or is it just tossed each year as part of the cost of doing business (racing)? How long can they last? Will the stock fuel-pump work OK?

[Foxie]

You bring up a curious variant to my group buy.

Today with modern tires and emergency tire inflators is it really necessary to have a spare tire? I have often thought of putting a larger tank in the boot with the larger section going where the spare tire is/was located.

When is the last time you changed a tire and used a spare? Hey, if you or any of you want to consider a 13 or 15 gallon cell in the Elan, I am up for it. We could get it custom made to fit right across the bottom under the wood and you would not even see it. It would look like a normal Elan but you would increase your range by almost double.

Of course you do add weight of 7lbs or so per gal.

Perhaps we could somehow make a model out of foam or something of a tank that fills up the whole bottom of the boot. Would love to get others opinions, good or bad on this.

In 33 years of Lotusing, I don't think I have ever used the spare. Having recently changed to Ford bolt-on hubs, I now carry a 13 x 3 spare, gives a bit more luggage room.

Regarding putting a fuel tank in the spare wheel recess, I think that 15 gals x 7lbs = 105 lbs might be a bit too much load on just a light fibreglass moulding. I have had to repair the boot where the exhaust hanger started ripping the fibreglass.

And in a rear end collision it would be very, very vulnerable

[tvacc]

I agree on the vulnerability. But that is there whether you have an 8 gal tank back there or a 15 gal. tank. That is why I like putting a cell back there. At the rear, right over the hot muffler.....time in a burn ward is not good time. A cell with a bladder and foam is meant to give you time to get out of the car. And to stop it from blowing on compression and leaking upon metal rupture.

Honestly, I have not driven an Elan without a cell since the early 90's. I jus bought a a 26R clone and it does have a cell from the UK with foam,just a can with foam but I honestly think that without a bladder you might be kidding yourself.

But I do agree on the weight. It might not be a good idea. Anyone else have any input?

[tvacc]

I have thought about a bladder tank with some sort of dry-break inlet/outlet and might consider buying in even though I have a brand new alloy tank on the shelf. Questions: the foam is for anti-surge for racing I think, how would it behave with old gas? Can one clean a bladder tank or is it just tossed each year as part of the cost of doing business (racing)? How long can they last? Will the stock fuel-pump work OK?

The foam is more to stop the compression of the gas, or the gas hitting the side of the tank with such speed and force that the tank explodes. At least that is what I have been told. The foam has no affect on gas, new or old. the bladder is to keep the tank from leaking on being hit or compressed. Basically it is all meant to give you time to get out of the car.

I have had cells in my Elans since the 90's and although I sold those cars, I did own them for quite a while. I never had to replace the foam in those. I have two cells in my Caterham that the first I put in about 1995 and the second about 2002 or 2003. An upper 7 gal. which sits right behind the rear bulk head and a 7 gal that sits in the stock location. I carry 14 gallons of gas in my Caterham. I can switch back and forth from cell to cell. I used a Ford truck fuel switch valve.

The flip over valve is to stop the fuel from leaking out if you should flip. It goes at the top of the cell but at the bottom of the fuel pipe that comes down from the filler.

Anyways you are supposed to send the tanks back for inspection every 5 years to keep them current for racing. My people tell me that if you are not racing, they are good for about 5-7 years, I had my bottom Caterham cell spring a leak about 9 years after I put it in. I send it back for another bladder and foam. My upper cell in my Caterham is about 12 years old and honestly I am just waiting for it to fail. I do drain the cells every winter storage and I only use non-ethanol fuel in them whenever possible. But you can use ethanol 10% but supposedly they do break down faster.