E30 Zone

I've been thinking about fuel tank stuff since I recently had to remove mine again, and although it wasn't a particularly strenuous task on my track car I couldn't help but think this would be easier if the thing was in 2 halves. For short sprint racing and track day stints, removing the entire N/S section of the tank would mean that weight can be saved and also I don't have to spend an hour dismantling the underside of the car to remove it if required for what ever reason. I'm assuming here the larger section on the drivers side is ~30L and the smaller half on the passenger side is ~20L??

From there I was thinking however that due to the work I do with endurance racing, some of the club level long distance races would be good to do as well which brings back the need for the extra capacity.

What I'm proposing is that the two halves be separated with an extra mounting point for each be added and the two be linked by flex lines which would allow the passenger side part to be removed and capped if only running short distances or if that tank had to be removed?

Does this sound like a good idea to other or should I just stop thinking?

There's the whole plava of getting it welded up once it's been cut, which is a risk of explosions, plus making sure you've got all the holes plugged up as well.

If you've still got your spare wheel well, could go with a tank that fits in that, or go with a ATL bag tank, considering you're thinking about racing it, a bag tank would be a good idea for safety reasons as I'm sure you full well know.

Edit: ATL even do one it seems!

http://www.atlinc.com/saver-cell-series.html

I do have a 30L ATL tank on the shelf which I acquired a few years ago the problem is for weight distribution and safety the standard tank is in a very nice place; low down in the middle of the car. I've seen an E30 have its rear end smacked with a fuel tank in the boot and it just burst into flames.

As for modding the tank I don't think there would be much work, separating the two halves just needs the 'bridge' part cutting down. The link pipe at the bottom can be capped with proper dash fitting caps the only but that would need figuring out is the link breather pipe across the top but iirc that rubber any way? Unless I'm missing something and the chambers are linked across the top too???

Something like this:

Braided hoses would work to cover the bridge. But you'd have to have a connection at the bottom of the tank to have the balancing effect between them. Might be possible with some aero spec connections and a dry break connector.

If the mounting of the two sections was correct there's no reason why the standard link pipe could not be used but yes a flexi version with some dash fittings would be just as easy. I'm fitting a pump out dry break any way so the tank would be pumped out after each run/day to keep en eye on fuel consumption etc.

was thinking the same but only running with the drivers side of the tank in place and fitting a small swirl pot and external pump under the back passage side

With my car being lhd I was hoping to balance the car.

crossie wrote:was thinking the same but only running with the drivers side of the tank in place and fitting a small swirl pot and external pump under the back passage side

With my car being lhd I was hoping to balance the car.

This is what im working on exactly

How far have you got with it Andrew?

Im just looking at how to split the tank and seal it, but then ive been carried away with possibly a custom bag and a kevlar 'tub' This is only since my new found dry carbon skillzz.

Demlotcrew wrote:Im just looking at how to split the tank and seal it,

Is it not as straight forward as it first seems with separating the two halves?.

Demlotcrew wrote:
but then ive been carried away with possibly a custom bag and a kevlar 'tub' This is only since my new found dry carbon skillzz.

Nice work

Thanks dude, getting there, can finally stand on the lip without it flexing.

The tank will split really well actually, my issue is with how to secure it as there will only be three bolts (IIRC), which may be enough, possibly one more bracket at the centre above the prop may secure it well.

I would also flat floor on the opposite side as a lot of air will 'damn' there at speed.

Andrew

If you look at the photo I posted above, the 3 mounting holes on the right hand side are in a 'triangle' so I recon you could be ok. The othe side would need some attention in order to do what I'm proposing though.