ally fuel tanks.. baffles/foam/sump/ int collector???

[lowly106]

firstly my apologies for this not being an ultima based query but 106+saxo sites are more based to "big rims" and something called "ICE?????"

after seeing some of your cars at the open day last year and from reading this orum a bit i`ve come to the conclusion that, quite frankly, you know your s**t... so.....

i find myself requesting your help...

ally fuel tanks!!!

well with the tank box nearly finished in my car:



i turn my attentions to the tank itself..


ATL( and any other bag type) is WAAAAAAaaaaaay outta my price league so its gonna be ally..

now from what i gather as its feeding an injection engine i either need an internal collector and a high pressure pump.. or run a low pressure pump from the tank to a swirl pot then high pressure pump to feed the engine..
both methods are to avoid air getting into the fed fuel????...

idealy i`d like to avoid using 2 pumps and a swirl pot as its extra fabrication for me and extra cost in aeroquip fittings...

i`ve seen a setup in a pro-alloy tank that uses a collector:





now is this merely a tank inside a tank or is there something cleverer involved?? the site mentions 1 way check valves???:



(which i assume allows fuel into the collector but not out)

seeings as the stuff you guys build on here get slung about all over the place are there any other methods or advice you can give?? parts suppliers?? i know a few of you gents have modified the fuel side of things in the ultimas so any help would be greatly recieved....

cheers
stu

[Steve_D]

The tank within a tank is, as you say, a trap where fuel can enter but not exit hence the one way valves.
I take your point about the extra bits like the swirl pot and all the fittings but the cost of the tank-in-tank is going to be very high and will require a specialist to build.

I would go:-

• Foam filled tank with a sump in the bottom from which you draw the fuel. The foam reduces surge and gives some explosion protection.
• External low pressure pump.
• Filter
• Swirl pot
• High pressure pump
• Filter
• Regulator.
• Etc.

The benefits are there is nothing to go wrong with the tank once it is in place and everything else is on view and easy to maintain or swap out in the event of a failure.
If this is a race car then the sump should be placed to one end of the tank to make the most of the surge.

Steve

[rdodger]

I had mine made by Bryn at Allyfab.

All alloy, baffled with internal swirl pot. The fuel return comes in the bottom of the pot to refill it and draws fuel from the tank in with it.

The fuel pump fits in the spring clips.

It is very well made and wasn't too expensive.





Before the swirl pot it used to starve in long left handers once it was down to half a tank.

Now it will keep on going till it's empty.

Edited by rdodger on Sunday 31st May 16:04

[andygtt]

I designed and made my own alloy tank and put internal baffles and foam in my tank similar to whats shown... but im still going to have an external swirl pot, guess it depends how hard you think the car is going to corner and how highly tuned the engine is, if its gone have large sticky tyres on, handle like a touring car and spend loads of time on track you dont wana skimp and not fit an external swirl pot.... if its a very fast road car ala an Ultima or Noble etc, then maybe you dont and you can just weld in some cleaver baffles and trap doors to trap the fuel by the pump.

edited to add that the external swirl pot is probably the safest and simplest method and unless you are running 400+bhp wont be that expensive as you can get the extra pump and swirl pot for about £150 including fitting if your careful were you buy from.

Edited by andygtt on Tuesday 2nd June 08:52